# Fuel Pump and Fuel Sender Guides



## ViperOneZero (Sep 4, 2008)

*Dashpod or fuel sender fault*

The TT 225 is now ageing and as a result people are frequently seeing fuel level faults. What you need to determine is what is at fault. It is usually 1 of 2 things- either the dashpod failing, or faulty fuel senders.

Plug in Vagcom. Select instruments ( ch 17 ) Carry instrument output tests. The needle should smoothly rise to full, then drop to half then empty. Does your needle line up correctly during the test? if not then your pod is likely to be goosed.

Does your erratic fuel level mirror the dis readout? ie does the dis miles to go value rise and fall as per the needle? if it does then the fault likely lies with the fuel sender sending erratic signals to the pod.

If upon a dashpod change or fuel sender change your fuel needle reads in reverse, that means you have placed the incorrect fuel senders in the tank or fit a dashpod which is coded to read the opposite sender values to the ones you have installed.

The 2 sender types are

Vehicles up to 05.02 
float at lower end position approx. 59 Ohms 
float at upper end position approx. 282 Ohms

Vehicles as of 05.02 
float at lower end position approx. 282 Ohms 
float at upper end position approx. 59 Ohms

Unfortunately Audi have appeared to have a pat number error as the post 2003 senders arrive with pre 2003 resistance!

There can be rare occasions where only one of your senders will fail. If this happens your needle will sit at half way ( or thereabouts )

*Removing the Fuel pump and Senders*

There are 2 fuel devices on the TT. The primary pump , which is electrically driven is situated behind the drivers seat on a UK RHD vehicle. There is a secondary unit situated behind the passenger seat. This is not powered, but is connected up by way of a pipe, and sender electrical connector. Both primary and secondary fuel pumps units have a fuel sender attached.

As daunting as it may seem removing the fuel pump form the TT is quite a straight forward job.

The best guide I have found is here: http://forums.audiworld.com/showthread.php?t=1951856

Here is a brief vid of the pump 




and a fuel sender guide: http://public.fotki.com/RoberTT/maintenance/repairing_fuel_sender/

*Fuel Sender Issues*

When you need to remove the wiring clips form the sender, please ensure that you don't try and pull them off without placing a sharp object as indicated below to press a small retention clip down.










If when you have switched the sensors over your fuel gauge is reading zero, there will be a bad connection on the clips.. you will need to remove and get to work with a multimeter, to ensure that the senders are operating correctly, and that the signal is reaching the wiring beyond the clips.



















Secondary pump and sender unit-









You can try cleaning the sender circuit board using a toothbrush etc.. and http://www.maplin.co.uk/isopropyl-alcoh ... 2d&c=73669.

IMPORTANT:

IF ORDERING NEW SENDERS THROUGH AUDI- ENSURE THEY MATCH YOUR OLD ONES- IE THE DIRECTION OF THE BLACK ITEM ON THE PCB http://i4.photobucket.com/albums/y109/gunnergibson/Fuel Sender Guide/FUELFLOATANDSENDER.jpg

AUDI HAVE INCORRECT PART NUMBERS FOR THE SENDERS, THEY DON'T ACCEPT RETURNS- TAKE YOUR SENDER TO THE DEALERSHIP BEFORE YOU PAY, CHECK GOODS


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## caney (Feb 5, 2004)

Nice post mate,most cars over 7 years old will have degraded fuel pumps so its worth replacing the pump which comes as a complete unit inc senders etc.my dis would never read above 200 miles even when filled up but now its spot on,worth doing.


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## ViperOneZero (Sep 4, 2008)

The sort of pump you need for your car is the one you,d use to fill an olympic pool up in 5 mins flat.


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## caney (Feb 5, 2004)

GunnerGibson said:


> The sort of pump you need for your car is the one you,d use to fill an olympic pool up in 5 mins flat.


Ha ha not quite,just run another inline uprated pump


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## a13xbb (Jan 27, 2007)

Do you haver the part no's for the senders(2003) car! im pretty sure mine need changing!


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## techfreak (Aug 13, 2010)

does the fuel pump 8L9919051J and 8L9919051K come with the sender as a combo?

is it worth just replacing the whole part instead of the sender, then only for the older pump to fail later?

are those part no's above correct for pre 2003 motors?


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## ViperOneZero (Sep 4, 2008)

I will post up the sender part codes shortly.

The post 2003 (primary ) senders Audi supply have been ballsed up somewhere in the supply chain

When you order a secodary fuel pump , it comes complete with a sender. Im not sure about the primary fuel pump.


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## a13xbb (Jan 27, 2007)

GunnerGibson said:


> I will post up the sender part codes shortly.
> 
> The post 2003 (primary ) senders Audi supply have been ballsed up somewhere in the supply chain
> 
> When you order a secodary fuel pump , it comes complete with a sender. Im not sure about the primary fuel pump.


Did you ever dig out the sender part codes?


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## S&amp;S (Mar 29, 2009)

Has anyone got a guide to getting to these in a roadster?


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## ViperOneZero (Sep 4, 2008)

Somneone stated this on another thread:

my mechanic had to do this once and he didn't know how to get to the fuel pump / sender so I had to take my laptop along to show him. You take the central rear panel off then the two side panels. Then you have to take the central subwoofer housing off which then leaves access to a small black dinner plate sized disc which is the opening to the fuel tank and to the pump / sender.

another guide:

http://www.ttforum.co.uk/forum/viewtopic.php?f=2&t=173606&hilit=fuel+pump


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## tomdennis (Jul 26, 2011)

My fuel gauge is all over the place but it does seem to change in unison with the distance remaining so on the information in your excellent piece my problem points to my sender units.
I have removed both of the sender units and have checked the resistance, the primary pump sender varies from 30 ohms with the arm down to 149 ohms with the arm up and the auxiliary sender has similar readings. Would these figures indicate that they are both shot and could be the cause of my readings ?
many thanks


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## tomdennis (Jul 26, 2011)

I have had a further thought GunnerGibson, do the ohms readings that you have indicated refer to each individual sender or both of them connected up to each other? When I do connect them up and take readings they are about the same as the ones you have indicated.
Thanks.


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## ViperOneZero (Sep 4, 2008)

Hi ,

did you follow the guide form the start? ie using VAGCOM needle sweep to determine that the needle sweep tests are carried out correctly? The main issue is cancelling out the possibility that the pod is at fault.

Give the senders a good all clean with switch cleaner.

then go from there


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## nickls13 (May 10, 2011)

Thanks For posting this mate, as I (still) haven't gotten around to fitting the one I got from you yet.
Now I will. 
When the weather dries up!


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## ViperOneZero (Sep 4, 2008)

nickls13 said:


> Thanks For posting this mate, as I (still) haven't gotten around to fitting the one I got from you yet.
> Now I will.
> When the weather dries up!


here is my neighbouring town 21/6/12


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## Tritium (Apr 25, 2011)

Floods are no problem here.... :lol: 
The main road traffic lights just round the corner:


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## tomdennis (Jul 26, 2011)

Thanks for that Gunner, whilst my two sender units were out(after a days work) I just wanted to make sure they were 100% before I put them back especially as the symptoms point to faulty senders rather than a faulty dashpod.
Hope your abode is not threatened, thanks Tomdennis.


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## dizzle (Mar 22, 2009)

My fuel sender is stuck at half way on the gauge and dis, from what I've read here it means one of the fuel senders need to be replaced, now is this the one by the fuel pump or the second one? also anyone know the correct part number as i believe my current one is not the correct fuel sender? i am running 2002 225 Quattro


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## AuntyJean (Mar 19, 2013)

I have the same problem (same make, model, year).

How can I tell when I need fuel?


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## Hoggy (May 8, 2002)

AuntyJean said:


> I have the same problem (same make, model, year).
> How can I tell when I need fuel?


Hi, Put 4 gallons fuel in, reset trip meter, 100 miles later put more fuel in.  
Hoggy.


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## Foolee (Nov 3, 2013)

Mod's this should be a sticky. I just double checked with ECS tuning and I ordered the wrong sending unit. That certainly explains why my fuel gauge has been all wonky. Now to burn off this tank of gas and to pull the pump again so I can swap sending units... [smiley=gossip.gif]


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## Trig (Jun 7, 2013)

The distance on the computer is right, the guage seems to start at half a tank (emtpy) and then stop when it hit the stop for full tank, ignition off the guage drops to empty as I would imagine.

More little bits to fix, amazing how a woman has a car and gives it to a man and "theres nothing wrong with it", had the car since Tuesday, so far fixed the washer bottle, sender for fuel is next, then front disks/pads, belt/haldex due at the end of the year as well....


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## Hoggy (May 8, 2002)

Hi Trig, If Fuel range (miles to MT) & gauge show the same incorrect reading, it's usually the level senders in tank, otherwise it's a dashpod prob, From what you've said it's your dashpod & not the level senders.
Hoggy.


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## Trig (Jun 7, 2013)

Hoggy said:


> Hi Trig, If Fuel range (miles to MT) & gauge show the same incorrect reading, it's usually the level senders in tank, otherwise it's a dashpod prob, From what you've said it's your dashpod & not the level senders.
> Hoggy.


Cheers chap, given the temp seems to be out as well I was leaning towards the dash anyways, good to hear the same from some one who actually knows wtf they are doing


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## Shotgun (Jan 7, 2013)

Hi, I replaced my dashpod, but not everything is working properly. The speedometer was originally in miles and I wanted to change it to a dashpod in Km.

When I adapted the new dashpod to the car via vagcom, the speedometer reading is correct but the fuel level is opposite (because the dashpod is coded to the opposite fuel level sender).

When I flash the new dashpod with the old dash's eeprom the fuel gauge is correct, but the speedometer is out about 30% (because it is internally still coded to the miles/h dash).

Does anyone know how to make the adaptation for either the opposite fuel level sender, or change the speedo coding from miles to Km?

Or does anyone have any other ideas?
Thanks


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## Shotgun (Jan 7, 2013)

Anyone have any ideas? I guess replacing the fuel level sender with an 03 or newer would fix it.
Or flashing the dashpod with the cluster dump from an 02 TT with a speedometer in Km.... Does anyone know where I could find that?
Thanks


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## srebe (Jan 27, 2016)

Does anyone know whether I can replace the fuel level sender on a 2002 TT quattro coupe without completely removing the primary fuel pump? I am hoping not to have to disconnect the hose to the secondary pump (behind the driver seat) so as not to have to also remove that secondary pump to fish the connecting hose out (or reattach it). Also wondering if it just lifts out, or if I have to twist and unlock it to remove it? Thanks for any info.


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## Hoggy (May 8, 2002)

Hi, According to Bentley Manual.
Fuel Level resistances are..

*2 wheel drive. up to 05/02*
low tank 54 ohms
Full tank 290 Ohms
*05/02 onwards.*
Low tank 290 Ohms
Full tank 54 Ohms.

*All wheel drive up to 05/02*
Right hand sensor
low tank 29 Ohms
Full tank 147 Ohms

*05/02 onwards*
Low tank 147 Ohms
Full tank 29 Ohms

*Left hand sensor up to 05/02*
Low tank 27 Ohms
Full tank 140 Ohms

*05/02 onwards*
Low tank 140 Ohms
Full tank 27 Ohms

Hoggy.


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## srebe (Jan 27, 2016)

I took a reading of the primary pump sender (right side) and got zero ohms, which I assume means the float is dysfunctional. The secondary (left side) fuel level sending unit has not plug on top to check with the meter. So I'm just guessing it's the primary. Parts guy at the dealer said it's a PITN enough of a job that I should do both at the same time. But I'm hoping just changing the primary sender would be path of least resistance - if I can get to it without removing the entire primary pump.



Hoggy said:


> Hi, According to Bentley Manual.
> Fuel Level resistances are..
> 
> *2 wheel drive. up to 05/02*
> ...


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## Hoggy (May 8, 2002)

Hi sreb, As you connecting meter to terminals No 2 & 3 the 2 middle ones & pushing float down or pulling up, when checking resistance
Does you Fuel Range give the same but incorrect reading as the dash gauge.
Hoggy.


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## srebe (Jan 27, 2016)

Thanks for the reply - no, my gas gauge has been pinned to Empty for months, with the fuel alert lit up on the dash. Yesterday I filled the tank and took the readings from pins 2 and 3. But I didn't open up the pump to actually move the float. I thought that if it read zero ohms when the tank is full, that meant the float was not working.



Hoggy said:


> Hi sreb, As you connecting meter to terminals No 2 & 3 the 2 middle ones & pushing float down or pulling up, when checking resistance
> Does you Fuel Range give the same but incorrect reading as the dash gauge.
> Hoggy.


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## Hoggy (May 8, 2002)

Hi srebe, Does your fuel range read zero ish, as well as gauge.
Hoggy.


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## srebe (Jan 27, 2016)

Yep, range reads zero, and the gauge reads empty. For a while, prior to a month ago, the gauge would waver between full and half full, but never go below half full, and the needle would jump around from full to half full in seconds. Then I tried resetting the gauge by pulling the fuel pump fuse, then turning ignition on for 30 seconds, then off again. Since I did that the gauge has read Empty, gas mileage reads 0, and tank symbol displays.


Hoggy said:


> Hi srebe, Does your fuel range read zero ish, as well as gauge.
> Hoggy.


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## Hoggy (May 8, 2002)

Hi, O.K. must be the level sender/s then.
Hoggy.


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## srebe (Jan 27, 2016)

Thanks for confirming! I was ready to try replacing it but am spooked by the complication of the 2nd fuel level sending unit on the left side. Looking at a picture of that unit and reading how it hooks up, it sounds like it adds a lot more opportunities to break something. That's why I am wondering if I can half-remove the primary pump to get at the float, without disconnecting anything other than the primary pump's white cap/flange.



Hoggy said:


> Hi, O.K. must be the level sender/s then.
> Hoggy.


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## mainairmark (Jan 31, 2018)

I've had this problem on my new TT mk1. But I fixed it in 1 minute. Pull out fuse number 15 and number 28. Turn on the ignition but don't start the engine. You won't be able to start it anyway with the fuses out. Then, key out and put the fuses back in.
Job done. :lol:


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## Terry63 (Apr 23, 2018)

My distance computer works but gauge reads half full when empty and full on a full up is this a dashpod problem

Sent from my iPhone using Tapatalk


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## Hoggy (May 8, 2002)

Terry63 said:


> My distance computer works but gauge reads half full when empty and full on a full up is this a dashpod problem Sent from my iPhone using Tapatalk


Hi, If Fuel range (miles to MT) & gauge show the same but incorrect reading, it's usually the level senders in tank, otherwise it's a dashpod prob. From what you've said it's your dashpod.
Hoggy.


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## outdoor stevie (Nov 24, 2013)

Hello Serb, in order to get the level float gizmo out then you need to remove the primary pump and carefully fold the leveller elbow on itself to get it out of the tank hole, there's not too much to remove or break so you should be ok, try and get as much fuel used up before you start the job so that it's as low as possible when your hands go in to the tank and you don't want to spill any in the backseat area as it will smell for a long time.

Stevie


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## thebronze (Aug 15, 2020)

I swapped My cluster for a working one and now the fuel gauge reads in reverse... Can you just swap the wires on the in tank senders to rectify the issue?


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## Hoggy (May 8, 2002)

thebronze said:


> I swapped My cluster for a working one and now the fuel gauge reads in reverse... Can you just swap the wires on the in tank senders to rectify the issue?


Hi, Unlikely, but try it & then we'll know.
The resistance values changed in May 2002.
Is this a quattro TT?
Hoggy.


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## Wachu (May 6, 2019)

Hoggy said:


> thebronze said:
> 
> 
> > I swapped My cluster for a working one and now the fuel gauge reads in reverse... Can you just swap the wires on the in tank senders to rectify the issue?
> ...


Hello Hoggy,

I apologize for reviving this thread, but i need to make sure.

I own Quattro model from 2000 and i just replaced both sending units with new ones, that have 54-290 resistance. In result the gauge shows i have 3/4 of tank while it is empty. And i am very confused. Do i need the 54-290 resistance for the fuel pump and the 29-147 for the second unit? That is how it should work?

I could not find any informations about part numbers or other stuff and you are the only person i can ask for that.

Thank you in advance.


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## Hoggy (May 8, 2002)

Hi Wachu, The resistance value for your year should be.
29 Ohm empty to 147 Ohms full.. Sensor one
27 Ohm empty to 140 Ohms full.. Sensor two 
Hoggy.


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