BigBob00'TT

Well I have been leaking coolant lately. I didn't even know I was till the temperature light came on one day and I was slightly overheating while at a stop to almost 3/4! It would go back down to normal once I started driving. When I got home, I noticed my coolant level was extremely low. Topped it off and didn't have any flashing lights or overheating problem for a few days till again, overheating at a stop every now and then and flashing light. Checked the levels and again where low. Checked all around and couldn't see any leaking around the tank. Started searching around and alot of threads said linked it to the headgasket!! =(

Well great news!! All that needs replaced is the coolant hose flange. It connects into driver side head.
http://www.ecstuning.com/Audi-TT_MKI...ange/ES279315/
I didn't check on that side because I'm still pretty new to Audi and did not know coolant entered on the driver side.
I know this post is kind of pointless, but I just wanted to tell you guys and anyone with a coolant leak/overheating to check all hoses/flanges for leaks before deciding on it being your headgasket. The local Audi dealer told me that these flanges can crack easily and one small crack can leak coolant like crazy! So if you are having any kind of leaking problem check the coolant hose flange first!

AudiMick

Head gasket failure is pretty rare on newer Audis.

In order of likelihood.

Coolant flange.
Water pump.
Oil cooler

MosTT

Also add afterrun coolant pump at top of radiator on passengers side. I repaced mine recently.