My temp gauge has been acting up lately it goes to the center when its warmed up but lately it has been 1 line below the center line then it goes to the center sometimes it stays other times it goes back to that mark. What could cause this? By the way I have the green top sensor.

 

The guage is not linear. Meaning, your coolant changes one degree, the guage moves an entire notch. Don't worry about it. When it gets colder outside, expect it to say 1 notch cooler. Mine does the same thing and I just had my cluster replaced.

 

Mine did the same thing. I had the thermostat replaced and now it stays at the center mark.

 

Mine has been doing the same thing for around a year. I had the cluster changed but it made no difference. It drives me insane! I have taken it to two dealerships but they can't find what is wrong with it - I suspect it doesn't do it when idling.

TT 225 Roadster 2003

 

no i think it still does. Thank god I haven't had massive problems like other TT owners I just get all the damn little things with mine that drives me nuts.