# Overheating mystery solved:TT1.8 Owners beware



## lagmaster (Jul 7, 2011)

My TT had been running a bit too hot for several weeks, and no one seemed to be able to find the problem. The temp gauge would often creep over a notch-and-a-half past the middle in traffic, and even when the fans went on, the needle would struggle to move back to the middle. I had pressure loss in the cooling system, but nobody could find the leak. After flushing the radiator, changing thermostats, etc. I began to assume the problem was some faulty gauge or something like that, especially after I read in forums that several other TT owners experienced the same problem.
Long story short, my oil pressure light went on last week, and I sought advice from this forum. I was immediately urged to check my oil pressure and to remove the sump and check for clogging and pump damage. This saved my TT's life: Oil pressure showed normal, but I dropped the sump anyway and found sludge clogging the pickup screen. Damage to the engine was minimal--will need a new tensioner and that's about it. But guess what? After I changed the oil pump, gasket and screen, THE OVERHEATING PROBLEM DISAPPEARED!!
Turns out (according to my mechanic), that my clogged screen was only affecting the oil pressure intermittently, especially when the car got hot, because crud from the pan would float around faster in the hot oil and get trapped on the screen until the flow was obstructed so much that pressure would drop and the junk would fall off! This is the only reason my car never got hot enough to spell complete disaster. What seemed to be low oil pressure caused by overheating, was actually overheating caused by low oil pressure. So if your mk1 is experiencing cooling problems that all the flushing and thermostats and hose replacements in the world can't seem to cure, I suggest you remove the sump and check for the deadly SLUDGE. It is a hassle, but it very well may save your engine's life.


----------



## lagmaster (Jul 7, 2011)

BTW, I still have that small coolant leak. Even if it is a gasket, it doesn't seem to matter any more. The car runs as cool as when I first bought it, and I see no oil in the water, or vice versa. I just add a half liter of g12 or water every 600 miles and everything is hunky-dory


----------



## graham225 (Apr 5, 2004)

Interesting read, thanks for the heads up.


----------



## horneteer (Oct 21, 2008)

Thanks for sharing. So before the fix the needle on the temp gauge was often in the red zone (being over a notch-and-a-half past the middle), is that correct? Just trying to work out if I should drop my sump and have a look. Mine creeps past 90, up to about 104 deg C sometimes. But never into the red zone.


----------



## StevetS (Feb 26, 2011)

Thanks for the heads up - will bear this in mind for potential future problems!


----------



## lagmaster (Jul 7, 2011)

horneteer said:


> Thanks for sharing. So before the fix the needle on the temp gauge was often in the red zone (being over a notch-and-a-half past the middle), is that correct? Just trying to work out if I should drop my sump and have a look. Mine creeps past 90, up to about 104 deg C sometimes. But never into the red zone.


Yes, the UK version is calibrated a bit differently, from what I understand (I am in the US), but mine was showing about 105C., and never went into the red. Now it remains at about 90C maximum. Don't know if you have the same problem I had, but it won't hurt to look--If you have the time. It took me about 5 hours (a lot of bolts), but I suspect that someone who knows what they're doing could do it in about 90 minutes. The sludge problem is supposedly even more common on the 225Hp version.


----------



## Gone (May 5, 2009)

Cheers for sharing
Presumably you need a new gasket for the sump and the oil strainer in order to remove?


----------



## lagmaster (Jul 7, 2011)

badyaker said:


> Cheers for sharing
> Presumably you need a new gasket for the sump and the oil strainer in order to remove?


Yes, there is a thread in this forum that I used to find instructions on how to do the whole thing, but now I can't seem to find it. I believe it was charlie or TT 51 that sent me to it


----------



## horneteer (Oct 21, 2008)

lagmaster said:


> horneteer said:
> 
> 
> > The sludge problem is supposedly even more common on the 225Hp version.


Anyone know why the sludge problem might be more common on the 225 than other models?


----------



## lagmaster (Jul 7, 2011)

I think it may be because the 225 may make the turbo work a little harder, or simply because 225 owners like to drive a bit faster--just a guess


----------



## TT51 (Feb 28, 2009)

lagmaster said:


> badyaker said:
> 
> 
> > Cheers for sharing
> ...


Glad you got it sorted mate without any terminal damage. It's a common problem coming up quite regularly now.

Phil you don't need a gasget on the sump just a smear of sealant all round. Audi will rape you for it but an automotive gasget sealant is fine, not silicon sealant though. I can't for the life of me remember if there was a seal on the pickup, pretty sure there was but don't be alarmed if I'm wrong as it's inside the sump and bathed in oil. You will be able to tell when ordering the pickup. You can actually just clean the metal gauze in the pickup but a new one is only £9.

Here is the thread I linked to viewtopic.php?f=2&t=178279&start=60


----------



## lagmaster (Jul 7, 2011)

Actually, here in the US the metal gasket cost me $30, and the sealant was $55--that's why they call them stealers!!!
I don't think my old gasket was damaged at all, but Audi told me it always needs replacement. Reading this post above by TT51 makes me very angry for once again being conned by the dealership. 
My new advice as an amateur TT owner is: Never buy OEM unless an Audi expert who DOES NOT work at the dealership says you should.


----------



## Gone (May 5, 2009)

I used Loctite 5920 on the rocker cover, after a thread on that job somewhere - if it's good enough for John-H, it's good enough for me. Reckon that would do the job then? I'm sure when I did my oil change recently I saw some sort of gasket in there though :?


----------



## TT51 (Feb 28, 2009)

100% sure mate NO gasget on the sump the loctite you speak of is good for the job :wink:


----------

