well i'll give it a shot.... I don't think it's the sensor b/c when i changed the coolant and let it drain all the way out, the temp went to the 1 tick mark after the mid. After I put in coolant it went back down. I know i just don't have the ratio right

 

ratio doesn't affect temp like that. I already said, I run straight water sometimes in the summer, and the gauge reads the same.

If the coolant sender was exposed to air (by you draining the coolant with the car running... hot...) then theres a small chance you baked it and its reading wrong now. This is why you need to check and see what the car is actually seeing for temps vs. what the gauge shows. There are 2 circuits, one for ECU signal, one for the gauge. If they're not the same number, (12 o'clock position on gauge being 190°) then you know the sender is bad.

 

Close to 2 years ago when I had the timing belt, h2o pump, and all that good stuff changed the mechanic did not mix the coolant with water. Instead he used straight coolant... Guess what... car ran fine. Last Winter when that fire hydrant jumped into the middle of the road, and I had to get a new radiator (along with other things) the body shop used straight G12 then as well. Still no problems with my TT running one tick hot, or one tick cold.

Could just even be the coolant temp sensor that's on the fritz.

 

well damn... I guess my sensor is bad. I am getting the timing belt change done this summer, so I hope to just wait till then since they should change it.

 

thermostat could be changed with the timing belt. Temp sender is not. Its a cheap part, and a 5 minute job. Sender is on the driverside of the engine, mounted in a plastic piece that bolts to the block. Obviously, coolant lines run to it, so it shouldn't be hard for you to find/replace.


Yours might be black, they failed a lot, and the revision is a 'green top'. These part numbers might not be correct though, its just a pic i pulled off the net.

 

Well i guess i'll have to go and buy this part. Can i get it online, at autozone, or is it strictly an Audi dealer part?? Does anyone have a picture under the hood of where this goes on a 2001 tt quattro 225 hp?

 

try ECStuning.com and you should be able to find it easily with the description I gave in my last post.

 

I'm not sure about the green ones, but my TT had a blue one. When it went bad I picked up a new blue one at the local Ford parts department for $25.
Same price as ECS, just without the shipping fees and waiting...

Oh yeah just make sure you remove the old o-ring, and replace it with a new o-ring.
If the new part doesn't come with one, you can pick one up at any local parts store, walmart, etc..

 

Thank you for all your help!! Does anyone have a link to where this part is located exactly?? Or a previous forum with a pic, or a pic that they took themselves of the engine bay that they could put a red arrow pointing to the general viscinity?? Thank you.