Temperature gauge not working

[Kaapse_Laaitie]

My temp guage is playing up. Most times it doesn't move from cold start. other times moves to about 70-80 degrees. wots up with this thing?

[s4-99]

Sounds like it could be the temp sensor/switch. When mine played up i had this changed at my local specialist and i've not had a problem since.

Hope this helps, i'm sure someone else will give you more info or same info

[Kaapse_Laaitie]

Does it affect the car's performance i.e ECU?

[UKS4APR1]

The temp sensor is a 4-pin dual sensor, one part for ECU other part for Temp gauge. Usually the sensor for ECU goes faulty, causing difficulty starting car from HOT (TOO RICH - ECU thinks engine is cold). In your case (and others) the gauge plays up. Cheap and very easy to change, there is now a superseded part.
Having said that, Audi are known (especially TT's) for having problems with their dash instruments!!
Don't worry - probably the sensor, worth changing in any event as it's a known fault.
Do a search, you'll find plenty of references.

[Harley]

My temperature guage is doing a similar thing... fluctuating between 90 and 60...

Oil temp stays constant and the car runs fine. Looking to get that changed at the next service (1500 miles time).

I'll let you know how I get on if you haven't sorted it by then...

[Dippy]

The sensor in question is the G62. The "good" one has a green body.

[Kaapse_Laaitie]

Has anyone changed this sensor by themselves? If yes ... where is it located and how easy/difficult is the job?

[UKS4APR1]

A lot of people have changed this themselves, it's very simple.
Do it with engine cold and there's no problem with any water loss.
You should take a look here........... http://forums.audiworld.com/s4/msgs/2317718.phtml

[UKS4APR1]

Here's a pic to help you locate the sensor
http://209.128.70.155/ECTsensor.jpg

[Kaapse_Laaitie]

Here's a pic to help you locate the sensor
http://209.128.70.155/ECTsensor.jpg

Thanks a lot UKS4APR. I'll attempt the job once I have the sensor. Will let you guy know how it goes.

[KayGee]

Bear in mind that is the rearview of the engine, so when searching for the sensor look at the rear left hand side from the front of the car. It's underneath the the MAF to Y pipe accordian hose. Easy to do, make sure you get a new O ring and that the old O ring is removed before refitting.

[SimonS4MTM]

You will also need a new retaining clip as the old one can break easily when puting it all back together