Engine Temp Guage Not Moving

[just8250]

Hello All,

2008 Audi Q7 S-line temp gauge not moving and CEL light on. Coolant level is a little low, coolant level check comes on for first 5 minutes then once the water portion heats and expands, indicator light turns off. I replaced the sensor for the coolant temp (at the top of the hose leading into the radiator) but this did not help. I am getting heat as I should and the car appears to be running normal, just cant figure out what other sensor or maybe the thermostat would affect the gauge from reading. Any ideas?

[CarlosSpcyWner9]

If the car is heating up and you're getting heat within a few minutes of driving (of course it depends on how cold/hot it is outside), it most likely is not your thermostat. If the engine is running very rich when it is at operating temp, then your sensor could be bad. Btw when the engine is cold the map sends a lot more fuel to it so it runs safer while it is getting up to operating temperature (some people don't understand that). But if it is running well at operating temperature, then it could be something with the gauge being wired up on the dashboard not getting the signal.

My advice is to get a scanner, find out what code it is throwing, if it says something is wrong with the thermostat, fix it. A good thing to do is use the scanner to view the data of the car and its sensors to check what the engine temperature is reading. If it has a ludicrous number for the temperature (high or low) then it could be your sensor is bad. If it is not changing at all and you notice the car is heating up (because the heater works), then it could also be the sensor.