I have a 2004 A4 3.0 V6 Quattro Convertible, and just recently the engine coolant warning light has come on.

So here is what happens, up to about 10-15 minutes of driving, the engine temp gage is sitting at normal (needle straight up), then all of sudden it climbs to the 3/4 mark, which then the coolant light comes on, but then it stays at the 3/4 mark, never hitting the red zone.

Based on my symptoms, does that sound like a faulty thermostat, water pump,
sensor?

Any help would be appreciated.

Thanks

 

from the owners manual

 

Turns out it was just a sensor.