# car won't start after de-cat UPDATE!!!.....FIXED,!!!



## brian1978 (Jul 10, 2013)

Fitted a decat (gutted standard exhaust) with lambda tricker, went to start the car and it started then died. Now it's just turning over. Like no fuel. Car has a 85miles on display to empty and I'm sitting on ramps at the moment.

Going to scan it in a few minutis when laptop charges a bit.

Any ideas?


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## DCorker (Dec 1, 2013)

brian1978 said:


> Fitted a decat (gutted standard exhaust) with lambda tricker, went to start the car and it started then died. Now it's just turning over. Like no fuel. Car has a 85miles on display to empty anemia sitting on ramps at the moment.
> 
> Going to scan it in a few minutis when laptop charges a bit.
> 
> Any ideas?


Strange.

Might sound daft but you've not left anything disconnected that may have done so prior to the job as a precaution.

The car should start with no exhaust on (mine did anyway).


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## brian1978 (Jul 10, 2013)

Car won't scan 

Tried to scan block 1 it says no response from controller.

Other blocks seem ok. Scanned xenon range and it read the block fine.


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## brian1978 (Jul 10, 2013)

DCorker said:


> brian1978 said:
> 
> 
> > Fitted a decat (gutted standard exhaust) with lambda tricker, went to start the car and it started then died. Now it's just turning over. Like no fuel. Car has a 85miles on display to empty anemia sitting on ramps at the moment.
> ...


The only thing I disconnected was the lambda sensor, it would still start if I damaged it removing it?


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## NickG (Aug 15, 2013)

Definitely will start without the cats, mine was exhaust-less starting the other day. Not knocked something in the bay? Also try clearing everything with your reader. Mine wouldn't start until I cleared everything!


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## NickG (Aug 15, 2013)

Sorry didn't realise it wasn't scanning properly! Ummm does it turnover alright? Not a dead battery problem is it?


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## DCorker (Dec 1, 2013)

brian1978 said:


> The only thing I disconnected was the lambda sensor, it would still start if I damaged it removing it?


Hmm - I'm not certain. Hopefully someone can clarify, but i'd be tempted to suggest it might not start if the lambda is damaged. But should give an error code


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## brian1978 (Jul 10, 2013)

NickG said:


> Sorry didn't realise it wasn't scanning properly! Ummm does it turnover alright? Not a dead battery problem is it?


Turning over fine.


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## Adam86 (Nov 20, 2013)

If the lambda has shorted out i know on a few cars it can blow the ecu fuse? Could be worth checking if you can't scan for any faults


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## NickG (Aug 15, 2013)

Checked fuse 28 for the fuel pump? Connections to injectors?


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## L33JSA (Jun 30, 2010)

Adam86 said:


> If the lambda has shorted out i know on a few cars it can blow the ecu fuse? Could be worth checking if you can't scan for any faults


This ^


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## brian1978 (Jul 10, 2013)

NickG said:


> Checked fuse 28 for the fuel pump? Connections to injectors?


Seem ok, it is block 01 I should be checking, right?


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## brian1978 (Jul 10, 2013)

L33JSA said:


> Adam86 said:
> 
> 
> > If the lambda has shorted out i know on a few cars it can blow the ecu fuse? Could be worth checking if you can't scan for any faults
> ...


Where is the ecu fuse lee?


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## Hoggy (May 8, 2002)

Hi, Check fuses No.10,29,34,& 43. all to do with engine management.. 32 is injectors.
Hoggy.


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## Adam86 (Nov 20, 2013)

Also remove the lambda tricker! And check that the lambda wires are ok before changing any fuses.


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## Stevey83 (Oct 16, 2011)

My bros lambdas on his car shorted against the chassis a wile ago. Car refused to start. Disconnect the live and see if it sparks against battery. If not you've got a short. As said also check fuses first.


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## brian1978 (Jul 10, 2013)

Stevey83 said:


> My bros lambdas on his car shorted against the chassis a wile ago. Car refused to start. Disconnect the live and see if it sparks against battery. If not you've got a short. As said also check fuses first.


Sorry, disconnected live lead on battery?


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## brian1978 (Jul 10, 2013)

Thanks for the help fellas. Going to call it a night and pick this one up tomorrow, fed up and it's raining. [smiley=bigcry.gif]

Anyone know where the Ecu fuse is though, I checked all the others on the side of the dash, all looked fine.


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## Stevey83 (Oct 16, 2011)

Yes the live off the battery.


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## brian1978 (Jul 10, 2013)

Stevey83 said:


> Yes the live off the battery.


It sparked a tiny amount.


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## Stevey83 (Oct 16, 2011)

Depends on how much tiny is. I would have thought you would see quite a few sparks if there was no short. See if you can find a YouTube video of how it should look

Have you tried disconnecting the lambdas and starting.


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## brian1978 (Jul 10, 2013)

Stevey83 said:


> Depends on how much tiny is. I would have thought you would see quite a few sparks if there was no short. See if you can find a YouTube video of how it should look
> 
> Have you tried disconnecting the lambdas and starting.


Not yet. Sparks were tiny, like static electricity sparking. I'll check you tube. I'll disconnect lambda and try.


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## c4z (Aug 15, 2011)

ECU fuse is fuse 37 I think..


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## Stevey83 (Oct 16, 2011)

37 is the radio.


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## Adam86 (Nov 20, 2013)

Iv just done a quick search and the Ecu fuse which looks like its quite common to blow is fuse 10
I could be way wrong tho as It was a quick search.


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## Stevey83 (Oct 16, 2011)

Try fuse 10 and fuse 29 for ECM


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## L33JSA (Jun 30, 2010)

Hoggy has already given you all the fuse number you need to check.

If you cant scan the ECU and all fuses are fine then you may have blown the ECU.

Have a look what you are missing - fuel or spark.


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## Hoggy (May 8, 2002)

L33JSA said:


> Hoggy has already given you all the fuse number you need to check.
> 
> If you cant scan the ECU and all fuses are fine then you may have blown the ECU.
> 
> Have a look what you are missing - fuel or spark.


Hi, I don't know why I bother :roll: :wink: 
Hoggy.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> Hoggy has already given you all the fuse number you need to check.
> 
> If you cant scan the ECU and all fuses are fine then you may have blown the ECU.
> 
> Have a look what you are missing - fuel or spark.


I'll check tomorrow after work. Thanks lee. Fuses looked fine.

Could a shorted lambda blow an ecu? If I have done this is it dealers to get it fixed?


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## L33JSA (Jun 30, 2010)

brian1978 said:


> Could a shorted lambda blow an ecu? If I have done this is it dealers to get it fixed?


No....myself and others just made that up to lead you on a wild goosechase!! :roll:

Not at all - used ECU off eBay and code it to your car using VAGCOM.


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## LOWTT225 (Oct 13, 2008)

brian1978 said:


> Fitted a decat (gutted standard exhaust) with lambda tricker, went to start the car and it started then died. Now it's just turning over. Like no fuel. Car has a 85miles on display to empty and I'm sitting on ramps at the moment.
> 
> Going to scan it in a few minutis when laptop charges a bit.
> 
> Any ideas?


Try dropping it Down off the ramps it may not have as much fuel as you think!


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## L33JSA (Jun 30, 2010)

LOWTT225 said:


> Try dropping it Down off the ramps it may not have as much fuel as you think!


Man raises a valid suggestion.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> brian1978 said:
> 
> 
> > Could a shorted lambda blow an ecu? If I have done this is it dealers to get it fixed?
> ...


That's refreshing. Do I need full vagcom or can I do that with lite?

And hoggy, I did acknowledge your advice and appreciate it. I checked them fuses, they look ok visually, I'm going to check them properly using a meter tomorrow.

Once again sorry for the barrage of questions, I'm useless with electrics and appreciate all the help.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> LOWTT225 said:
> 
> 
> > Try dropping it Down off the ramps it may not have as much fuel as you think!
> ...


One of the first thing I tried, reason I didn't drop it immediately is I have to use 2 large planks of wood on the ramps to clear the spoiler, they stop it rolling easily backwards, I bumped it using the starter in reverse to get it off and level. If only it was that easy :?


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## Stevey83 (Oct 16, 2011)

L33JSA said:


> brian1978 said:
> 
> 
> > Could a shorted lambda blow an ecu? If I have done this is it dealers to get it fixed?
> ...


Just a short in the electrics will cause problems. I would say a blown ecu is highly unlikely.


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## brian1978 (Jul 10, 2013)

Stevey83 said:


> L33JSA said:
> 
> 
> > brian1978 said:
> ...


I disconnected the lambda at the mutiplug, still won't start and vcds won't read the ecu.


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## spaceplace (Mar 10, 2013)

doesnt vagcom work with just the ignition on (car doesnt need to be started to perform some tests) if that is the case and you cant scan/read anything using vagcam with just the ignition on then wouldnt that mean its electrical and not a fuel or spark/engine issue but a problem with the ecu?


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## brian1978 (Jul 10, 2013)

Was looking into replacing an ecu, more confused now than before. Some sites saying they are plug and play as long as the last letters In part number match. Others saying I have to get immobilizer defeater codes :?

I'm really hoping it's just a fuse I missed [smiley=bigcry.gif]


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## spaceplace (Mar 10, 2013)

i would have thought a fuse would blow before the ecu, guessing you've checked the ones on top of the battery, i dont know if they are to do with the ecu or not but worth a look.
good luck hope its an easy fix.


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## spaceplace (Mar 10, 2013)

could be worth disconecting the battery for half hour as well - just to see if it clears it self


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## brian1978 (Jul 10, 2013)

spaceplace said:


> could be worth disconecting the battery for half hour as well - just to see if it clears it self


Is been disconnected all night I'll try it.


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## brian1978 (Jul 10, 2013)

brian1978 said:


> spaceplace said:
> 
> 
> > could be worth disconecting the battery for half hour as well - just to see if it clears it self
> ...


Still just turning over. Nothing

I could hear the throttle body aligning after I connect the battery, if the Ecu was bricked would it still do that?


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## spaceplace (Mar 10, 2013)

seems a strange one, does the dash light up all ok with ignition? any warning lights? can you hear the fuel pump when turning ignition on?


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## L33JSA (Jun 30, 2010)

brian1978 said:


> I could hear the throttle body aligning after I connect the battery, if the Ecu was bricked would it still do that?


Depends what part of it was cream crackered although it does sound more positive.

Now you need to find out what it's not getting - fuel or spark.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> brian1978 said:
> 
> 
> > I could hear the throttle body aligning after I connect the battery, if the Ecu was bricked would it still do that?
> ...


I don't think it's getting fuel Lee, I pulled the return pipe off the rail and cranked it. A very small amount came out and the engine caught for split second, it didn't actually run but sounded like it tried, could this be because the pipe was off it allowed a small amount of fuel to be pulled through?

Would a squirt of easy start confirm this? Don't like using that crap but would it confirm ignition?



spaceplace said:


> seems a strange one, does the dash light up all ok with ignition? any warning lights? can you hear the fuel pump when turning ignition on?


Everything else works :?


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## Stevey83 (Oct 16, 2011)

Can you here fuel pump prime?


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## LOWTT225 (Oct 13, 2008)

Have you been welding anything?


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## Stochman (Aug 16, 2013)

Feck Bri, what you done to her? Hope you get it sorted pal, I'm pretty sure there's enough in the way of TT brains on here to get you back up and running. I'd love to help but unfortunately I don't think my single brain cell will be of any use. :roll:


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## NickG (Aug 15, 2013)

If its still not letting you scan it there has to be an issue there surely? I remember after priming the engine it wouldn't let me start it until i cleared all the codes... if you can't get yours to scan then there could be codes there preventing start-up?

As to why it won't scan though i have no idea?! :?:


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## steveupton (Mar 23, 2010)

brian1978 said:


> Would a squirt of easy start confirm this? Don't like using that crap but would it confirm ignition?


As you say, it is crap but will confirm if it's a fuel starvation issue or not. This is the way we proved the same fault on my step sons TT when his fuel pump failed without warning. If it is fuel starvation, can be other causes such as fuel pump relay or blockage.

Sorry to see you've got this problem especially after all the work you've put in.


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## brian1978 (Jul 10, 2013)

LOWTT225 said:


> Have you been welding anything?


No only thing I did was remove the post cat lambda. I forgot to disconnect the battery before I worked on the car. I normally do this, it took a LOT of force and persuasion. Like others said maybe damaging it could have caused issues.


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## brian1978 (Jul 10, 2013)

steveupton said:


> brian1978 said:
> 
> 
> > Would a squirt of easy start confirm this? Don't like using that crap but would it confirm ignition?
> ...


Thanks m8, these things happen I suppose. I'll give it a try.


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## Peeunit (May 22, 2013)

A long shot:

Theres not anything causing a massive restriction in the exhaust system is there? Like something in this new Cat that has caused a blockage? Thus causing a back pressure preventing the engine cranking?


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## brian1978 (Jul 10, 2013)

Peeunit said:


> A long shot:
> 
> Theres not anything causing a massive restriction in the exhaust system is there? Like something in this new Cat that has caused a blockage? Thus causing a back pressure preventing the engine cranking?


Nah the cat section is a gutted standard exhaust, you can see daylight through it.


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## c4z (Aug 15, 2011)

brian1978 said:


> L33JSA said:
> 
> 
> > brian1978 said:
> ...


So could it actually be low fuel caused by the ramp/angle then?
Crap in the fuel filter caused by angle of car?
Can you hear the fuel pump prime? I believe there are 2 pumps - a second one to transfer fuel over the tunnel, under the back seat.
Fuel pump relay ok?
Have you checked the run of the fuel line for damage - esp if you were in that location banging about under the car..?


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## brian1978 (Jul 10, 2013)

c4z said:


> So could it actually be low fuel caused by the ramp/angle then?
> Crap in the fuel filter caused by angle of car?
> Can you hear the fuel pump prime? I believe there are 2 pumps - a second one to transfer fuel over the tunnel, under the back seat.
> Fuel pump relay ok?
> Have you checked the run of the fuel line for damage - esp if you were in that location banging about under the car..?


I doubt it's because of the ramps, had a 1/4 tank in it and I've had it on ramps tons of times with less fuel in it. When I tried to start it it ran for about 5-10 seconds and died. Not just cut off but struggled and wouldnt rev then died. It then started very briefly again then nothing just turns over.

I will listen for the pump priming when I get home, it's just a 3 second buzz from the back seat?

Where's the fuel pump really. And how do I check it.

Never thought about damaged fuel lines. I don't think I did, I just removed the exhaust wasn't any banging about I drilled bolts off but wasn't near fuel lines at that time. I will check them though but prob need to wait till Sunday.

Thanks for the ideas.


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## NoMark (Jul 6, 2011)

brian1978 said:


> c4z said:
> 
> 
> > So could it actually be low fuel caused by the ramp/angle then?
> ...


That does sound like it's fuel related.

Fuel pump is in the tank, under the rear seats. You have to check that there is a live feed to it with a meter I think. That will obviously require the assistance of a willing helper to turn the ignition on once you're ready with your meter.


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## brian1978 (Jul 10, 2013)

NoMark said:


> brian1978 said:
> 
> 
> > c4z said:
> ...


I'm guessing the pump is on the opposite side to the sender thingy for the gauge. So drivers side?

I'll check this when I get home.

Still can't understand why it won't let me scan block 01 using vcds


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## Adam86 (Nov 20, 2013)

If your sure all the fuses are ok and it's not a fuel problem (although it does sound possible) there should be an ecu relay which would be the next thing I'd check out.


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## brian1978 (Jul 10, 2013)

Adam86 said:


> If your sure all the fuses are ok and it's not a fuel problem (although it does sound possible) there should be an ecu relay which would be the next thing I'd check out.


Where can I find the Ecu relays?


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## Adam86 (Nov 20, 2013)

Wish I could tell you, I'm not fully clued up with the Audi yet. 
But my guess would be somewhere behind the battery.


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## NickG (Aug 15, 2013)

brian1978 said:


> Adam86 said:
> 
> 
> > If your sure all the fuses are ok and it's not a fuel problem (although it does sound possible) there should be an ecu relay which would be the next thing I'd check out.
> ...


Are they not in the black box that sits passenger side of the engine bay under the windscreen, next to the plastic waterfall?

I'm still thinking its to do with the electrics... you should be able to scan the car regardless of fuses etc.?


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## Adam86 (Nov 20, 2013)

NickG said:


> brian1978 said:
> 
> 
> > Adam86 said:
> ...


Yeh that's where I'm thinking, but I'm not sure if there's some behind the dash.

Car should scan regardless of fuses unless the ecu wasn't getting power and if the relay or fuse to the ecu hasn't blown then its quite likely the ecu has been fried! (Hopefully not the case though)


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## NickG (Aug 15, 2013)

In that picture the relays are directly up from the Maf sensor, you can just make out the black box.


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## Stevey83 (Oct 16, 2011)

I doubt it's anything like a relay, unusual for a relay to suddenly fail.

Have you tried another key, could be possible immobiliser fault.

Low fuel would obviously show on dash.

Did you disconnect both lambdas?

I'll put my money on a short and or blown fuse.


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## Adam86 (Nov 20, 2013)

Stevey83 said:


> I doubt it's anything like a relay, unusual for a relay to suddenly fail.
> 
> Have you tried another key, could be possible immobiliser fault.
> 
> ...


A short could cause damage to a relay just a easily as it could blow a fuse.


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## stillchillin (Oct 29, 2009)

Hope you get it sorted soon , myself I would put a gallon of fuel in the tank just to eliminate the possibility that fuel is low and the dashpod is telling lies......only costs a few ££££


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## brian1978 (Jul 10, 2013)

stillchillin said:


> Hope you get it sorted soon , myself I would put a gallon of fuel in the tank just to eliminate the possibility that fuel is low and the dashpod is telling lies......only costs a few ££££


Defiantly not that m8, I put £20 in it just before I started the work, deffo 1/4 a tank in it. Done maybe 5 miles since I last put fuel in.

I found that Ecu relay. How do you test a relay with a meter?

I haven't checked fuel pump etc as battery was flat from all the cranking, stuck it on a charge.



Stevey83 said:


> I doubt it's anything like a relay, unusual for a relay to suddenly fail.
> 
> Have you tried another key, could be possible immobiliser fault.
> 
> ...


I've triple checked all fuses using a meter, they are defiantly fine, checked fuses on the side of the dash and top of battery tray, any I've missed.

The only thing that could have shorted is the lambda. I only removed the one on the cat as it was only the cat back I removed. But if it was causing the car not to start wouldn't it resolve itself when I unplug it?


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## Paulj100 (Mar 24, 2009)

I can't be of much help but I wish all the best for you Brian. Hope you sort it soon.

Paul


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## Adam86 (Nov 20, 2013)




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## Skeee (Jun 9, 2009)

Re the relay, have a read:- viewtopic.php?f=2&t=523098


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## brian1978 (Jul 10, 2013)

Paulj100 said:



> I can't be of much help but I wish all the best for you Brian. Hope you sort it soon.
> 
> Paul


Thanks m8, thanks everyone I'll get to the bottom of if. The help has been awesome.


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## brian1978 (Jul 10, 2013)

I'm guessing this is the relay.

Tested it with a meter, zero ohms across the coil and beeps when I force it to contact.

142 ohms across the other 2 pins, the guy in the utube video showed 72 ohms across his, but it looked like a different relay. Pins looked different.

Does mine sound ok?


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## Skeee (Jun 9, 2009)

Does it click over when you start the car?
_Put a finger on the plastic case and you should feel it click._
If not remove the relay and voltage check the supply at the base. Which is from the ECU.


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## Adam86 (Nov 20, 2013)

brian1978 said:


> I'm guessing this is the relay.
> 
> Tested it with a meter, zero ohms across the coil and beeps when I force it to contact.
> 
> ...


The lower the ohms the better but a larger relay will have a higher ohms reading so that doesn't sound like its faulty to me. 
It's still sounds like an electrical problem but if all fuses and relays are ok you need to have a real good look around where you have been working for anything that has even the slightest damage. 
Also test for voltage at the fuses to make sure there connected properly and test for power to the relay terminals


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## brian1978 (Jul 10, 2013)

Skeee said:


> Does it click over when you start the car?
> _Put a finger on the plastic case and you should feel it click._
> If not remove the relay and voltage check the supply at the base. Which is from the ECU.


I take it you mean when I turn the key to one before the start position? To check the voltage do I removed the relay and test the contacts on the car with the meter?

I'm going to need to wait till tomorrow as the battery is on a charge.

Thanks m8.


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## brian1978 (Jul 10, 2013)

Adam86 said:


> brian1978 said:
> 
> 
> > I'm guessing this is the relay.
> ...


Yea I'll get the car up on jacks in the light, I was doing the work in the dark to finish it so might not have noticed something. I pinched the wires on the lambda against the heatshelding when trying to screw it into the tricker, I may have shorted something, I don't know.

But again if the lambda was causing it wouldn't it rectify it's self when I was unplugged at the multiplug?


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## L33JSA (Jun 30, 2010)

brian1978 said:


> Car won't scan
> 
> Tried to scan block 1 it says no response from controller.


I'm putting my money on this being the whole key behind it not starting.

Try this.....

1. Check and double check fuse 37 - use a multimeter
2. Check fuel pump relay - replace if necessary as they are only cheap. this doesn't only control the fuel pump but other circuits too.


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## Adam86 (Nov 20, 2013)

brian1978 said:


> Adam86 said:
> 
> 
> > brian1978 said:
> ...


shorting the lambda to any bare metal on the car will always blow something, so keep checking for fuses, perhaps there's a main ecu fuse close to the ecu?
A friend of mine recently tried pulling off a loose heat shield off on his civic and snagged the lambda wires and it blow a quite a large fuse which was wired inline with the ecu. The fuse wasn't located with any other fuses, so perhaps it could be a similar setup with the Audi.


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## Skeee (Jun 9, 2009)

L33JSA said:


> brian1978 said:
> 
> 
> > Car won't scan
> ...


 It is a big clue. If the ECU fuses are 100% good (I would check them again to confirm they are zero ohms) then carry out a voltage check at the input to the Motronic relay prev. mentioned as this may indicate the ECU has been damaged.



brian1978 said:


> ................... as the battery is on *a *charge. ................










Sorry! Couldn't resist._ In house joke._ :wink:



brian1978 said:


> Skeee said:
> 
> 
> > Does it click over when you start the car?
> ...


From page 5 of the topic previously quoted above:- viewtopic.php?f=2&t=523098&start=60


L33JSA said:


> It probably would have been extremely useful if you'd given the background behind the problem a bit sooner.
> I would say that there's a good chance you've got a faulty ECU- especially since it was not responding to the accelerator etc.
> One thing to try.
> Put your ear next to the relay and have someone switch the ignition on - can you hear the relay 'click' or not? If you hold it you should be able to feel it through your fingers too.
> ...


To check the Motronic Relay supply voltage, have a look at the diagrams posted on page 5 of that post and identify the supply and earth, and connect the meter in the DC volts range across those contacts. If there isn't 12vDC then remove the meter lead from the earth side and connect to a known good earth. Battery negative lead for example. This will check the earth line also._ (Thank Lee for that!)_


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## brian1978 (Jul 10, 2013)

Ok, we have progress. Got it started......

After reading Lee's awesome diagnosis on that other thread I decided to run a wire from pin 85 on the relay to the earth. The car started after a lot of cranking (near flattened the battery again, but it was only part charged) But revs are sitting high 1.3krpm and a bit lumpy, Which was a bad thing as this ment a new ECU on the other thread. 
I tried to start It again and nothing. Touching the makeshift earth off the -ve terminal did nothing, the relay won't click. So I pull it out to test it straight off the battery and it clicks. Plugging it back in it worked again. So I assume it's this and remove the earth and go to pack up. Out of curiosity I tried it again and started but the revs climbed tp 2krpm. I grabbed the laptop and the ecu scanned no problem. Here's the codes that return after I clear them. The fault in the relay shows but disappears after I unplug and put it back in.

First scan before I cleared them....










And after I clear them. That Ecu relay code reappears if I try when it won't click on startup. Removing and replacing cures it temporarily



















I notice the relay starts working after I unplug and put it back in. I can hear it click as I turn the ignition. Could this be a dodgy connector?

Here's the dash, I'm not touching the accelerator etc.....










So I'm guessing it's an intermittent fault with the connector for the ecu relay and this accelerator position sensor is borked???

Thanks again, off to Google the rest of the codes.

Edit.

17526 is the lambda unplugged.

17070 ECM Power Relay Control Circuit (J271): Short to Ground. I take it that's tyre relay.

18042 - Accelerator Position Sensor 2 (G185): Signal too High.


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## Stevey83 (Oct 16, 2011)

Could the relay be shot? Excellent news you got it started!!

Could your new cat mod be causing the high rpm. Are your lambas connected. What is a lambda tricker


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## brian1978 (Jul 10, 2013)

Stevey83 said:


> Could the relay be shot? Excellent news you got it started!!
> 
> Could your new cat mod be causing the high rpm. Are your lambas connected. What is a lambda tricker


I think the accelerator position sensor is causing it. The tricker is a mod to pull the lambda back from the exhaust, in theory the Ecu should think that the cat is present.


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## Adam86 (Nov 20, 2013)

Try some contact cleaner in the relay ports, it may have charred the terminals when shorting the lambda. 
Then plug the lambda in without the tricker and see what codes remain.


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## L33JSA (Jun 30, 2010)

Check the voltage in & out the relay. Probably worth replacing the relay too as it's only cheap.

If its a voltage issue due to possible resistance in the relay due to damage then the throttle body may not have aligned itself properly hence causing the other issue.

Low voltage can do very very strange things.


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## brian1978 (Jul 10, 2013)

I'll get a relay and get the battery fully charged, also clean the terminals try the lambda plugged in and do a TB reset. Off to bed now though I think I'll sleep a wee bit better knowing it's at least starting.

Fingers crossed this is it. I'll kept you updated.

Electrics is not a strong point for me. I'd still be scratching my head if it weren't for all the help. It's appreciated guys. [smiley=cheers.gif]


----------



## brian1978 (Jul 10, 2013)

Ok, I plugged the lambda back in this morning, full charge on the battery and tried to start it, won't start and Ecu won't scan block 01 again. I'm guessing the lambda is defiantly broken.

I tested the seat of the relay and it's showing 12.34v all the time, even with the ignition off, when I pull it out I can hear the contacts separating and clicking closed again when I put it in. I'm guessing this is not normal.

I'm going to remove and check all the wires in the lambda when I get home.


----------



## L33JSA (Jun 30, 2010)

The relay should only switch when the ECU sends a negative signal to it when the ignition is on afaik

Check to see if there is continuity between pin 85 and the negative battery terminal at all times or not because somehow it's managing to get a negative feed from somewhere.


----------



## brian1978 (Jul 10, 2013)

L33JSA said:


> The relay should only switch when the ECU sends a negative signal to it when the ignition is on afaik
> 
> Check to see if there is continuity between pin 85 and the negative battery terminal at all times or not because somehow it's managing to get a negative feed from somewhere.


Will do when I get home. Thanks again.


----------



## brian1978 (Jul 10, 2013)

L33JSA said:


> The relay should only switch when the ECU sends a negative signal to it when the ignition is on afaik
> 
> Check to see if there is continuity between pin 85 and the negative battery terminal at all times or not because somehow it's managing to get a negative feed from somewhere.


Unplugged the lambda again.

2 things. Pin 85 has no continuity when I connect the battery. When I turn the ignition on I hear the relay click, it won't go off till I disconnect the battery.

The meter shows no continuity on pin 85 right after I connect the battery, once I try to start the car or turn ignition enough to hear the relay click it shows 245 ohms. This remains until I disconnect the battery, simply turning the ignition off won't stop it.

Other alarming thing that happened, I tried a small squirt of easy start to see if the engine is getting spark. I cranked the engine a good 20 odd seconds then the red oil warning light came on. I immediately stopped.

Did this come on as no oil pressure was building as the engine wasn't starting, or do I have another issue?

I ran the engine a good 10 minutis last night while scanning the car, but no warning came on.


----------



## Hoggy (May 8, 2002)

Hi, Oil pressure is going to be low, when just turning on the starter.
Can't you just remove a coil pack, stick a spare plug in it & hold it on engine block while some else spins engine to see if sparks, that will prove if you have sparks.
Hoggy.


----------



## brian1978 (Jul 10, 2013)

Hoggy said:


> Hi, Oil pressure is going to be low, when just turning on the starter.
> Can't you just remove a coil pack, stick a spare plug in it & hold it on engine block while some else spins engine to see if sparks, that will prove if you have sparks.
> Hoggy.


Thought that was the case hoggy, still ages me about 6 months when I see a red oil warning light. :lol:

Don't understand why it started last night but now won't, bloody car [smiley=bigcry.gif]


----------



## jamman (May 6, 2002)

Brian I hope it gets sorted without too much grief.

It's a hard lesson learned to remove the juice when working on anything remotely electrical
we've all been there and made mistakes I know I have.


----------



## Hoggy (May 8, 2002)

Hi Brian, I know it has said before, but you must check for sparks & fuel.
Check for spark as suggested & then for fuel at injectors. Without one or the other it won't run reliably, but you probably know that.
Hope you get it sorted, but first you must determine what is missing, sparks or fuel.
Hoggy.


----------



## brian1978 (Jul 10, 2013)

Hoggy said:


> Hi Brian, I know it has said before, but you must check for sparks & fuel.
> Check for spark as suggested & then for fuel at injectors. Without one or the other it won't run reliably, but you probably know that.
> Hope you get it sorted, but first you must determine what is missing, sparks or fuel.
> Hoggy.


Both are missing hoggy. And the block 01 won't scan on vagcom, has to be something to do with the ECM relay as I could scan car and start when it appeared to work last night.

Thanks James, I'll be removing the battery connection for everything from now on.

I'll wait and see what lee thinks of the continuity readings in got earlier.


----------



## Skeee (Jun 9, 2009)

brian1978 said:


> Don't understand why it started last night but now won't, bloody car [smiley=bigcry.gif]


 Correct me if wrong, but,
it started last night because you provided your own earth return bypassing the earth(?) from ECU pin 21 to the relay.
* If this is a new relay* then I'd test the ECU earth from pin 21,
ie with the relay out, and with ignition on, 
voltage check from battery negative to relay base 5/85, looking for zero volts DC.
If it is zero then (and only then) confirm it on the Ohms range.
See wiring sheet 25/10 on page 5 of the link above.

The alternative to a spark check is to carry out a supply voltage check to the coilpack input.
_ (Which is fed from that relay)_
At pin 1 of the plug, input to the coilpack, black/purple wire. See sheet 48/10 (page 5 above link)
12v should appear with ign on, and occult with ign off.

A traditional spark check is more thorough as it will check the other four inputs to the coilpack. But if you don't have the 12v supply then they cannot work anyway.

If you do not have the 12v supply switching at the coilpack pin 1, it must be the relay or ECU, (or wiring between).
If it passes the 12v supply check you must confirm it with a spark check to suspect a fuel supply/pump issue.


----------



## Skeee (Jun 9, 2009)

brian1978 said:


> ... Pin 85 has no continuity when I connect the battery. When I turn the ignition on I hear the relay click, it won't go off till I disconnect the battery.
> The meter shows no continuity on pin 85 right after I connect the battery, once I try to start the car or turn ignition enough to hear the relay click it shows 245 ohms. This remains until I disconnect the battery, simply turning the ignition off won't stop it.


 Do this again with the relay out and carry out a DC Volts check first, because an Ohms check with the relay in place or with power on can produce spurious results.

This diagram shows fuse 10 supply's the relay 12v permanently. See above link page 5 wiring sheet 25/10, Link 120 above goes to Link 62 on page 25/10.


----------



## brian1978 (Jul 10, 2013)

Skeee said:


> brian1978 said:
> 
> 
> > Don't understand why it started last night but now won't, bloody car [smiley=bigcry.gif]
> ...


It's the same relay, I just wanted to try the car with a tb reset to see if it cured the high idle. I did the exact same thing and it's not starting now. It started ok last night without providing any artificial earth although it did start for the first time doing this, I just needed to unplug and puff back the ecu relay.


----------



## brian1978 (Jul 10, 2013)

Skeee said:


> brian1978 said:
> 
> 
> > ... Pin 85 has no continuity when I connect the battery. When I turn the ignition on I hear the relay click, it won't go off till I disconnect the battery.
> ...


Sorry skeee, this was with the relay out, took the readings from the relay seat.


----------



## L33JSA (Jun 30, 2010)

Last night I think was a fluke. It sounds like the relay is clicking consistently now. Have you checked the voltage OUT the relay?

Also it's worth noting that even if that ECM relay wasn't working you would still be able to scan the ECU as the other thread proved.

It's looking more and more like the actual ECU at fault......especially due to missing both fuel & spark.

Oil pressure light came on because you don't create enough oil pressure just by turning over on the starter.

Did you do my other suggestions with regards to fuse 37 & the fuel pump relay?


----------



## Skeee (Jun 9, 2009)

L33JSA said:


> Last night I think was a fluke. It sounds like the relay is clicking consistently now. Have you checked the voltage OUT the relay?
> 
> Also it's worth noting that even if that ECM relay wasn't working you would still be able to scan the ECU as the other thread proved.
> 
> ...


 +1 
If the ECU block doesn't scan, you do unfortunately, have to suspect the ECU.



L33JSA said:


> ...... Have you checked the voltage OUT the relay?............


 Pin 1 of the coilpack is the relay output. _See sheets 25/10 and 48/10._


----------



## Adam86 (Nov 20, 2013)

I'd be giving this a try now http://bit.ly/1isXeM8


----------



## brian1978 (Jul 10, 2013)

Skeee said:


> L33JSA said:
> 
> 
> > Last night I think was a fluke. It sounds like the relay is clicking consistently now. Have you checked the voltage OUT the relay?
> ...


Checked pin 1, it's showing zero volts on taking a reading after connecting the battery. After I turned the key to 1 before cranking the voltage read 12.6v. Then on turning the ignition off it remained 12.6v even after closing the car and locking it. The only way I stopped the voltage at the plug was to disconnect and reconnect the battery.



Adam86 said:


> I'd be giving this a try now http://bit.ly/1isXeM8


Yea, it says it's a remapped ecu, if I fit this and code it to the car will it reset the software to standard, or is this essentially the same as getting a generic map, surely it isn't that simple?



L33JSA said:


> Did you do my other suggestions with regards to fuse 37 & the fuel pump relay?


Yea fuse 37 is ok. Where is the relay?


----------



## brian1978 (Jul 10, 2013)

Checked fuse 37 again, it's fine and I'm getting 12v across the fuse plug.

Also I noticed I can't hear any fuel pumps priming.


----------



## Skeee (Jun 9, 2009)

Fuse 28 is also fuel pump fuse. http://www.wak-tt.com/fuses/fuses.htm


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## L33JSA (Jun 30, 2010)

brian1978 said:


> Where is the relay?


Under the drivers side dash just above the buzz bar. Its 4th relay in from the left on the bottom row. Numbered 167 or 409 I think.


----------



## brian1978 (Jul 10, 2013)

L33JSA said:


> brian1978 said:
> 
> 
> > Where is the relay?
> ...


Ok, do I need to remove the dash panel under the steering wheel to get to it?


----------



## L33JSA (Jun 30, 2010)

Preferably yes....alternatively you could always smash through it with a hammer..... [smiley=bigcry.gif]


----------



## brian1978 (Jul 10, 2013)

L33JSA said:


> Preferably yes....alternatively you could always smash through it with a hammer..... [smiley=bigcry.gif]


You don't know how close I am to that just now :lol:


----------



## Stochman (Aug 16, 2013)

L33JSA said:


> Preferably yes....alternatively you could always smash through it with a hammer..... [smiley=bigcry.gif]


 :lol: :lol: :lol:


----------



## Skeee (Jun 9, 2009)

Put the hammer down!


----------



## brian1978 (Jul 10, 2013)

Removed the relay and tested it, it seems fine. I can hear it clicking when I turn the ignition on.


----------



## L33JSA (Jun 30, 2010)

brian1978 said:


> Removed the relay and tested it, it seems fine. I can hear it clicking when I turn the ignition on.


ECU [smiley=bigcry.gif]


----------



## brian1978 (Jul 10, 2013)

L33JSA said:


> brian1978 said:
> 
> 
> > Removed the relay and tested it, it seems fine. I can hear it clicking when I turn the ignition on.
> ...


You think it's defiantly the ecu then, if it is, it's actually a relief m8, at least I know where to go from here.

So should I remove my Ecu and get the exact part number to order one from ebay. Will I need full vag-com to code it, the £99 version or will free one do?

Would I be better getting all the parts and paying a local Audi specialist to do it?


----------



## Skeee (Jun 9, 2009)

brian1978 said:


> ..............So should I remove my Ecu and get the exact part number .........


 Is the "scan pt no" not the same as the one printed on it?
Mines a 2005 225 Quattro Roadster pt no 8N0 906 018 CG. (Pt no from a Vagcom scan)
Don't know re compatibility issues with different part nos,
http://nefariousmotorsports.com/forum/i ... 11.0title=

http://www.ebay.co.uk/itm/audi-tt-mk-1- ... 1364861259
and
http://www.ebay.co.uk/itm/audi-tt-mk1-e ... 338a96ee49


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## L33JSA (Jun 30, 2010)

Yes, I think it's a very safe bet that that's at fault really.

Take your ECU out and get the proper part code off it just to be sure.

I wouldn't have thought the free VAGCOM would do it to be honest. Find someone who has it. If you pay an Audi specialist to do it you're likely to get shafted pricewise.

There's instructions on that other thread of how to do it.


----------



## L33JSA (Jun 30, 2010)

Skeee said:


> Is the "scan pt no" not the same as the one printed on it?


Yes it should be.

I'd take it out anyway....it might even rattle if you're lucky [smiley=bigcry.gif]


----------



## Skeee (Jun 9, 2009)

Prob already seen it but I posted some info re the ECU removal page 7 of:-
viewtopic.php?f=2&t=523098&start=90


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## brian1978 (Jul 10, 2013)

Skeee said:


> Prob already seen it but I posted some info re the ECU removal page 7 of:-
> viewtopic.php?f=2&t=523098&start=90


Jesus, why is it such a bitch to get the ecu out, [smiley=bigcry.gif]


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## steveupton (Mar 23, 2010)

It doesn't take that long to get to the ecu, you will need a small 2 leg puller, on old C type ball joint splitter or a special wiper arm puller to get the wiper arms off though. 20-30 mins max.


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## Peeunit (May 22, 2013)

You must be fairly close to pulling your hair out with this mate.

Hopefully you can take some solace from the fact that you could well have saved a couple of people from making the same mistake. 
Good on you for persevering with it.


----------



## brian1978 (Jul 10, 2013)

Peeunit said:


> You must be fairly close to pulling your hair out with this mate.
> 
> Hopefully you can take some solace from the fact that you could well have saved a couple of people from making the same mistake.
> Good on you for persevering with it.


Thanks m8. The help has been overwhelming, you don't realise how good this forum is till you really need it.

It's looking like I'm going to send my ecu off to be rebuilt. Another member pointed me in the direction of "the ecu doctor" I spoke to the girl on the phone and they will test it and repair it. This way it's a simple plug and play solution that won't require me coding a new ecu.

If it's not faulty they charge £50 for the test and it 100% rules that out, although I think I'm fairly certain it's pumped :lol:

Im also going to replace the lambda as a precaution before I plug anything back in.

Oh an ALWAYS disconnect the battery before even thinking about touching something remotely electrical


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## brian1978 (Jul 10, 2013)

L33JSA said:


> I'd take it out anyway....it might even rattle if you're lucky [smiley=bigcry.gif]


Well it's out, why did Audi feel the need to encase it in a mini safe secured with glued in shear bolts [smiley=bigcry.gif]

It didnt rattle but it does have a faint odour of cooked electrics.


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## steveupton (Mar 23, 2010)

brian1978 said:


> L33JSA said:
> 
> 
> > I'd take it out anyway....it might even rattle if you're lucky [smiley=bigcry.gif]
> ...


Smell of cooked electrics is not good and don't want to be the doom merchant but if the circuit board's badly damaged, may not be repairable.

Here's hoping it is though.


----------



## brian1978 (Jul 10, 2013)

steveupton said:


> brian1978 said:
> 
> 
> > L33JSA said:
> ...


Well they say they replace damaged circuit boards and in the testimonials there is a customer who got his fixed after an autoelectrician fried it. Suppose I'll find out soon enough. They say if they can't fix or test it they don't charge anything.

If they can't I'll just have to buy another one and get it coded somehow. I'm sure it's possible


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## steveupton (Mar 23, 2010)

Really hopes it works out, what a nightmare. TTs seem to be a bit like prima donnas, you love 'em and hate 'em in equal measures sometimes.


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## c4z (Aug 15, 2011)

Used the ECU Doctor in the past for a well fried Merc - fixed it a treat.


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## Stochman (Aug 16, 2013)

Good luck Bri, I'm sure it'll all end well


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## brian1978 (Jul 10, 2013)

Stochman said:


> Good luck Bri, I'm sure it'll all end well


Well it's in the post, see how it goes.


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## L33JSA (Jun 30, 2010)

jamman said:


> It's a hard lesson learned to remove the juice when working on anything remotely electrical


Potentially this wouldn't have helped him in this situation.

If he damaged the lambda wiring then having the battery connected whilst this happened is irrelevant really because as soon as he plugged the battery back in again the wires would have probably shorted causing the same issue.

Just one of those things really.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> jamman said:
> 
> 
> > It's a hard lesson learned to remove the juice when working on anything remotely electrical
> ...


While we are talking about said bstard lambda, I'm obviously going to replace it.

As it's going to be screwed into a fooler till I can get it mapped out do I need an expensive oem bosch one or can I getting away with a cheapo universal lambda from ebay?

http://www.ebay.co.uk/itm/Audi-TT-1-8-9 ... 4ace91ad93

There's that and you can get an even cheaper one you can solder on the plug from your old one.


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## L33JSA (Jun 30, 2010)

Why buy one at all if it's going to be mapped out. Just screw the old one in but don't connect it or buy a blank for the hole.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> Why buy one at all if it's going to be mapped out. Just screw the old one in but don't connect it or buy a blank for the hole.


Well it will prob be a few more weeks before I get it mapped now as getting this one fixed is prob going to cost me a few bob.

I was thinking more for getting rid of the dash light till then using the fooler. I'd imagine I'd need a custom map to get the light off so I'd be as swell saving a few more penny's for supporting mods to get the most from it.

Suppose I can just putt up with a light for a few months.

EDIT scratch that, I'll just put up with a dash light it's prob the fooler making the fit tight for the old lambda that pinched the wires and caused this whole problem.


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## spaceplace (Mar 10, 2013)

Mine's got a decat and a spacer and it still sets of the light, I just use my phone, (torque app) and a cheap Bluetooth to obd to turn it off, seems to come on every 50 miles or so

Sent from my LT26i using Tapatalk


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## Stevey83 (Oct 16, 2011)

I came from a Peugeot 206 to my TT. they could only have the EML light reset about 50 times, after that the EPROM memory in the ecu would be full, and the light could not be cleared. Is the TT the same?


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## brian1978 (Jul 10, 2013)

Stevey83 said:


> I came from a Peugeot 206 to my TT. they could only have the EML light reset about 50 times, after that the EPROM memory in the ecu would be full, and the light could not be cleared. Is the TT the same?


The TT is different. My wife has a 206, I know what you mean with the dash lights. Stupid stupid system.


----------



## ZephyR2 (Feb 20, 2013)

Although the owner of a new pretty Mk2 I've been following this thread and its been bringing back lots of memories from my younger days of the frustration, terror, unexpected expense and occasionally satisfaction of doing work on older cars.
I've got to admire your persistence in trying to sort it our yourself I would have handed it over to garage long before now I think. Its also really amazing the depth of knowledge and advice that's come from the other forum members - where do people get this information? Seems like some peeps have built their cars from scratch  Didn't anything like the internet in my younger days, but there again cars were a lot simpler to work on.
Anyway, I can't be of any help to you but I truly hope that you get that ECU fixed and that it gets you back on the road soon. Good luck.


----------



## Peeunit (May 22, 2013)

...... So, thats teh verdict mate? Any progress?


----------



## brian1978 (Jul 10, 2013)

Peeunit said:


> ...... So, thats teh verdict mate? Any progress?


Yep, fried pcb in the ecu caused by an electrical short. Kinda what I expected given the burned circuit board smell coming out of it. They've replaced the pcb and it's good to go.....

£238 with a warranty...... [smiley=bigcry.gif]

But should have the ecu in my hand by tomorrow 

Now. My questing is this, how can I be 100% sure the short did come from the lambda and it's safe to hook this ECU back up?

Is there any fool proof way of testing for shorts incase I fry this one?


----------



## Stochman (Aug 16, 2013)

Oh dear, sorry to hear that Bri, hopefully Lee or someone equally knowledgeable will be along shortly to answer your question, good luck mate


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## L33JSA (Jun 30, 2010)

brian1978 said:


> Now. My questing is this, how can I be 100% sure the short did come from the lambda and it's safe to hook this ECU back up?
> 
> Is there any fool proof way of testing for shorts incase I fry this one?


Simple answer....without testing every cable run to/from the ECU you can't.

On the plus side least you got a warranty with it [smiley=bigcry.gif] [smiley=bigcry.gif]

Have you stripped back all the insulation on the sensor to see if there are any breaks in there?

Would have been cheaper to get a used ECU off eBay though.


----------



## Adam86 (Nov 20, 2013)

brian1978 said:


> Peeunit said:
> 
> 
> > ...... So, thats teh verdict mate? Any progress?
> ...


As lee says there's no way in testing for short unless you are willing to spend weeks testing each individual cable. 
Just double and triple check the lambda wires before fitting your ecu. 
Fingers cross for ya mate hope this solves the problem and gets you back on the road. 
A lesson well learned for everyone here!


----------



## Stevey83 (Oct 16, 2011)

Pain in the arse but what about some kind of inline fuse from the lambda? Or would that not work.


----------



## brian1978 (Jul 10, 2013)

L33JSA said:


> brian1978 said:
> 
> 
> > Now. My questing is this, how can I be 100% sure the short did come from the lambda and it's safe to hook this ECU back up?
> ...


Yea probably, but then I'd have to find someone with full vag-com. I was quoted £150 bench time plus parts. Guess not much I can do, at least it's fixed and I know it's 100%.

I'm not going to plug a lambda in, ill get it mapped out when i get my remap done.
so just blank off the hole in the cat and treble check all the wires going to the lambda mutiplug.


----------



## Peeunit (May 22, 2013)

Good to hear mate... I'll cross my fingers for you tomorrow when u have to plug it in!!


----------



## brian1978 (Jul 10, 2013)

Ok now I'm paranoid :?

I'll check the lambda thoroughly. The guy at ecu doctor said something about it drawing current through an earth. Couldn't I plug the battery in and check all the earth wires going to the Ecu if I knew what pins were earths at the multiplug for the ecu?

:-|


----------



## Stevey83 (Oct 16, 2011)

We'll that would be your short, but as said could be any wire.


----------



## brian1978 (Jul 10, 2013)

Stevey83 said:


> We'll that would be your short, but as said could be any wire.


Suppose it's got to be, I never touched any other electrics. I'm going to wait till Sunday so I can thoroughly check every wire on the lambda.

Is it best to remove the wires going to the multiplug buy following them back to the loom and blinking them off completely. Or should I just tape up the end and put it inside the cover under the car?


----------



## Skeee (Jun 9, 2009)

brian1978 said:


> Ok now I'm paranoid :?
> 
> I'll check the lambda thoroughly. The guy at ecu doctor said something about it *drawing current through an earth*. Couldn't I plug the battery in and check all the earth wires going to the Ecu if I knew what pins were earths at the multiplug for the ecu?
> 
> :-|


 Of course current flows through the earth! How on earth (sorry) can it get back to the battery to complete the circuit.

With the battery negative and positive disconnected it might be worth testing the resistance from the Lambda positive supply to earth, and Lambda heater supply to earth, to rule out any obvious shorts.

According to the wiring diagram the Pre Cat Lambda is fed directly from J220 (ECU) pin 51, and return on pin 70, and the Lambda Heater is supplied from pin 5, other side of the heater is earthed.

The Post Cat Lambda is fed from pin 68 return on 69 and heater *earth???* is fed from pin 63 other side of the heater is a +ve supply from the activated charcoal filter system?

*EDIT :- See post after the wiring diagram!*


----------



## Skeee (Jun 9, 2009)

brian1978 said:


> Ok now I'm paranoid :?
> 
> I'll check the lambda thoroughly. The guy at ecu doctor said something about it drawing current through an earth. Couldn't I plug the battery in and check all the earth wires going to the Ecu if I knew what pins were earths at the multiplug for the ecu?
> 
> :-|


 If the post cat Lambda and exhaust is all you have disturbed then that has to be where you start checking.
Attempting to confirm all the Motronic (ECU) earths may be difficult as without a functional diagram of the internal workings it is difficult/impossible to know if there are any switched earths?


----------



## brian1978 (Jul 10, 2013)

Skeee said:


> brian1978 said:
> 
> 
> > Ok now I'm paranoid :?
> ...


Sorry skeee that's right over my head. I'm not great with electrics.

So testing the lambda +ve to earth and heater to earth I should see what, if it's shorted I should get continuity and if is not shorted I should get nothing?

You don't happen to have a wiring diagram for how the post cat lambda is wired?

Edit: thanks skeee. Mind reader


----------



## Skeee (Jun 9, 2009)

The Post Cat Lambda is fed from pin 68 return on 69 and heater *earth???* is fed from pin 63 other side of the heater is a +ve supply from the activated charcoal filter system?


----------



## Skeee (Jun 9, 2009)

brian1978 said:


> .................Edit: thanks skeee. Mind reader


 I can read minds but not that wiring diagram!  See the previous *EDIT *in RED.

My first check with the Lambda disconnected or removed would be a continuity check from Lambda Plug pin/socket 1 to the other three Lambda connections. They should all be open circuit if the ECU is unplugged.


----------



## brian1978 (Jul 10, 2013)

So the blue red wire on the lambda plug is the +ve supply. I'm guessing if I shorted it out it's this wire I've touched against one of the other 4 in the lambda wires.

As lee already pointed out, I need to carefully examine the lambda for signes of a short. What's worrying me is if I find absolutely no evidence of a short or anything untoward. What's to stop it instantly blowing again when I plug it in. It's not like it's a 50p fuse :?


----------



## Stevey83 (Oct 16, 2011)

Don't plug it in if you doubt it.


----------



## brian1978 (Jul 10, 2013)

Stevey83 said:


> Don't plug it in if you doubt it.


Catch 22.

What other option do I have?


----------



## Skeee (Jun 9, 2009)

brian1978 said:


> So the blue red wire on the lambda plug is the +ve supply. I'm guessing if I shorted it out it's this wire I've touched against one of the other 4 in the lambda wires.
> 
> As lee already pointed out, I need to carefully examine the lambda for signes of a short. What's worrying me is if I find absolutely no evidence of a short or anything untoward. What's to stop it instantly blowing again when I plug it in. It's not like it's a 50p fuse :?


Sheet 48-6 states Lambda Pin 1 is the Blue/Yellow wire on the BAM engine or Blue/Red on the ARY, AUQ, & AUM engines.
It also calls it a 4 pin connector. The pre cat Lambda has a 6 pin connector according to that page.


----------



## brian1978 (Jul 10, 2013)

Skeee said:


> brian1978 said:
> 
> 
> > So the blue red wire on the lambda plug is the +ve supply. I'm guessing if I shorted it out it's this wire I've touched against one of the other 4 in the lambda wires.
> ...


It's a bit difficult to make out.

I'll have a proper look over them tomorrow with a clear head. Thanks again skeee.


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## brian1978 (Jul 10, 2013)

J220 on that diagram, that's the ecu?

I can see how shorting a live on that would cook it.


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## L33JSA (Jun 30, 2010)

brian1978 said:


> J220 on that diagram, that's the ecu?
> 
> I can see how shorting a live on that would cook it.


Indeed it is.


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## brian1978 (Jul 10, 2013)

Am I being a paranoid idiot or would it be an idea to buy a cheap Ecu just to plug in to see if it cooks it again. I'm literally shitting myself incase I put my new unit in and it's still shorted out somewhere.

I could then sell it if all is good.


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## L33JSA (Jun 30, 2010)

It wouldnt be a bad idea at all.....BUT......how are you going to know if it's fried because the car won't start without being coded to the car which was the whole reason you got that one repaired.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> It wouldnt be a bad idea at all.....BUT......how are you going to know if it's fried because the car won't start without being coded to the car which was the whole reason you got that one repaired.


Am I right in saying vagcom shouldn't be able to read it if it's fried. I'd imagine even if it's a cheaper Ecu off a 180 I should still be able to put it in and scan it?

That and the smell of fried Ecu. It was obvious on my one it was cooked by the smell of burned pcb.

That "mapped" Ecu is still on ebay for £50 and it's the same code as mine.


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## L33JSA (Jun 30, 2010)

That's actually a good point - yes it should be able to read it if it's not fried.

Just imagine though....if you've got a bit of dodgy wire somewhere that isnt shorting when you are sat with your car on your drive...you fit the spare ECU and it's fine, then you fit your old ECU and it's fine....you drive off your drive...something moves and....zzzzzzzzz...PUFF......ecu fried [smiley=bomb.gif] [smiley=bomb.gif]

Sorry...... [smiley=bigcry.gif] [smiley=bigcry.gif] [smiley=bigcry.gif] [smiley=bigcry.gif] [smiley=bigcry.gif]


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## brian1978 (Jul 10, 2013)

L33JSA said:


> That's actually a good point - yes it should be able to read it if it's not fried.
> 
> Just imagine though....if you've got a bit of dodgy wire somewhere that isnt shorting when you are sat with your car on your drive...you fit the spare ECU and it's fine, then you fit your old ECU and it's fine....you drive off your drive...something moves and....zzzzzzzzz...PUFF......ecu fried [smiley=bomb.gif] [smiley=bomb.gif]
> 
> Sorry...... [smiley=bigcry.gif] [smiley=bigcry.gif] [smiley=bigcry.gif] [smiley=bigcry.gif] [smiley=bigcry.gif]


Thanks Lee :roll:

I'll be sure to wiggle plenty of wires before I put mine in.


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## brian1978 (Jul 10, 2013)

Do you think this one will fit for a test?

http://www.ebay.co.uk/itm/06A-906-018-G ... 2c6a132068


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## L33JSA (Jun 30, 2010)

Providing it's off a wideband,DBW, ESP variant 1.8T then yes it should.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> Providing it's off a wideband,DBW, ESP variant 1.8T then yes it should.


Bought it anyway. It's £8 delivered, worth a punt.

How can I find out, will it just not fit the multiplugs?


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## L33JSA (Jun 30, 2010)

brian1978 said:


> L33JSA said:
> 
> 
> > Providing it's off a wideband,DBW, ESP variant 1.8T then yes it should.
> ...


It'll fit but the pins will do different things and may even blow the ecu because there will be lives,negatives and signals in all the wrong places.

Still as you say worth a punt...


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## L33JSA (Jun 30, 2010)

....just bear in mind that if it does blow you won't know if/why it blew

If it doesnt blow then your other one still may do.


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## brian1978 (Jul 10, 2013)

L33JSA said:


> brian1978 said:
> 
> 
> > L33JSA said:
> ...


Problem is if it blows I won't know if it's because I have a short or if it's because it was the ecu. [smiley=bomb.gif]

I'll just sell this one again, should actually make money on it.

Probably best just to order a cheap bam ecu.


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## L33JSA (Jun 30, 2010)

Apparently these 'should' work for a BAM engine...

8N0 906 018 CG
8N0 906 018 H
8N0 997 018 PX
8N0 997 018 TX


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## Skeee (Jun 9, 2009)

Skeee said:


> Mines a *BAM *2005 225 Quattro Roadster pt no 8N0 906 018 CG. (Pt no from a Vagcom scan)


Google * " BAM ECU " * in quotes and a few turn up.


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## brian1978 (Jul 10, 2013)

Took the lambda off and inspected the wires, they look ok.

Now I'm no expert in lambda sensors but I'm guessing they shouldn't rattle :?

I sawed the end off it and bits of ceramic insulation??? Fell out. I'm guessing this is almost certainly my short.


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## stillchillin (Oct 29, 2009)

I'm sure I'm not the only one who looks on here every day hoping to see........Re car won't start after de cat..FIXED!!!!


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## brian1978 (Jul 10, 2013)

stillchillin said:


> I'm sure I'm not the only one who looks on here every day hoping to see........Re car won't start after de cat..FIXED!!!!


Thanks m8, fingers crossed for tomorrow.


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## Paulj100 (Mar 24, 2009)

stillchillin said:


> I'm sure I'm not the only one who looks on here every day hoping to see........Re car won't start after de cat..FIXED!!!!


+1. Fingers crossed for you Brian.

Paul


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## Skeee (Jun 9, 2009)

Paulj100 said:


> stillchillin said:
> 
> 
> > I'm sure I'm not the only one who looks on here every day hoping to see........Re car won't start after de cat..FIXED!!!!
> ...


 + another 1.







_ Crossed Christopher

Little Christopher crossed his fingers,
Then he crossed his toes.
Next he crossed his arms and legs
And somehow crossed his nose.
His body got so very crossed
That things weren't where they goes,
Now I'm afraid that he's so crossed
He can't fit into his clothes. _


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## James1050S3 (Sep 7, 2013)

Paulj100 said:


> stillchillin said:
> 
> 
> > I'm sure I'm not the only one who looks on here every day hoping to see........Re car won't start after de cat..FIXED!!!!
> ...


+2. I want to see a happy ending to this thread!


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## ExAudiSi (May 25, 2012)

Same here, I keep checking the forum every day hoping to see that your car is alive again


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## ades tt 180 (Jun 19, 2011)

Got my fingers crossed too...hope it works....would love to know what made it blow in the first place.


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## brian1978 (Jul 10, 2013)

ades tt 180 said:


> Got my fingers crossed too...hope it works....would love to know what made it blow in the first place.


Pretty sure it was me damaging the lambda when removing it. Looking at it, it looks like one of the 12v lives to either the sensor or the heater shorted to the earth. The earth is directly connected to the ecu.


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## Stochman (Aug 16, 2013)

+6 Bri, we all have our fingers crossed for you pal


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## Stevey83 (Oct 16, 2011)

+7. Sure it will be fine on restart.


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## mullum (Sep 16, 2011)

What happened to ...










and ..










?

Good luck mate ;-)


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## Stochman (Aug 16, 2013)

I lost count


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## brian1978 (Jul 10, 2013)

Thanks guys, Christ the pressure is on now :lol: :lol: :lol:

I really hope this goes ok.
I'll be honest I'm missing my car. I've had many cars off the road for various reasons. But never have I felt this longing to drive one again. 
Maybe I'm being sad, maybe it's because it's my TT.


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## c4z (Aug 15, 2011)

And..? Its been light for 2 hours ffs!!! :lol:


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## brian1978 (Jul 10, 2013)

Lol c4z, been eating breakfast and checking as many places for shorts as I can, I'm pretty sure it's good to go.










One question first. Pin 1 on the lambda which is pink blue on my car (diagram above posted said blue yellow) maybe I'm colorblind :lol:

Anyway, according time this, pin 1 should show continuity to earth and the other 3 should be dead, is this correct?

Should any be live, none are showing voltage. Maybe the Ecu needs to be plugged in?


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## brian1978 (Jul 10, 2013)

SHE LIVES !!!

[smiley=cheers.gif] [smiley=guitarist.gif] [smiley=mexicanwave.gif] [smiley=mexicanwave.gif] [smiley=mexicanwave.gif] [smiley=jester.gif]

Thanks to everyone for the support and kind words, especially skeee and Lee.



Runs rough but unplugging the maf sorted it, doubt it has anything to do with what happened. I'll get a new maf tomorrow.

Is it ok to run the car with it unplugged for a day?


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## ades tt 180 (Jun 19, 2011)

Yeay!...pleased for ya! [smiley=thumbsup.gif]


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## Adam86 (Nov 20, 2013)

Brilliant news! Iv been waiting all week to see this!
Well done mate!


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## jamman (May 6, 2002)

All's well that ends well.... not really sure wtf that means but there you go.

Good news Brian


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## mullum (Sep 16, 2011)

Yay !

So, will you buy a REAL decat or sports cat now


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## Hoggy (May 8, 2002)

[smiley=dude.gif].... [smiley=mexicanwave.gif].... [smiley=dude.gif] 
Hoggy.


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## ExAudiSi (May 25, 2012)

Thank goodness for that [smiley=mexicanwave.gif]

I can go outside and do some of my own jobs now :lol:


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## L33JSA (Jun 30, 2010)

Nice one.....it only took 14 pages haha


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## steveupton (Mar 23, 2010)

[smiley=cheers.gif] Well done for getting it sorted, hope that's the end of the problem.


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## stillchillin (Oct 29, 2009)

Just woke up in California to some good news...nice one..........


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## Skeee (Jun 9, 2009)

[smiley=mexicanwave.gif] [smiley=mexicanwave.gif] [smiley=mexicanwave.gif] [smiley=mexicanwave.gif] [smiley=mexicanwave.gif] [smiley=mexicanwave.gif]


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## c4z (Aug 15, 2011)

[smiley=dude.gif] [smiley=dude.gif] [smiley=dude.gif] [smiley=dude.gif]

Good news. I can sleep again!


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## Peeunit (May 22, 2013)

Well done mate!! You're a true inspiration, perseverance seems to be one of your strong points.
(I dont know how to get mexican wave guys, so have this ho! [smiley=gorgeous.gif]


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## Pugwash69 (Jun 12, 2012)

Before you buy a new MAF, see if blasting it with some brake cleaner helps? The wire in mine looked tainted before I cleaned it.

Glad there's life back in the thing though!


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## kasandrich (Sep 5, 2011)

Well done Brian, I bet there was some twitching going on when you turned that key 8)


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