Skip the auto shop - Our mechanics make house calls

Q: Coolant Temperature Gauge

asked by on

I have a 2007 Audi Q7 Premium 4.2 Engine. My temperature gauge is extremely slow to reach operating temp even after driving. I changed the coolant temperature sensor with a auto parts store sensor it helped briefly. Could this be because I need to use dealer oem part in Audi or a bad Tstat? Also the fan does not kick on to cool the engine after driving

My car has 106592 miles.
My car has an automatic transmission.

Hello. This potentially sounds like a combination of a faulty thermostat that may be stuck open and possibly a faulty coolant temperature switch that is causing the cooling fans to not come on. For a more precise diagnosis, I recommend having a local expert, like one from YourMechanic, to inspect the cooling system in order to have this correctly addressed.

Was this answer helpful?

This problem is likely caused by a failing thermostat. The thermostat is designed to restrict coolant flow to the radiator until the engine reaches designed working temperature (something close to 210 degrees Fahrenheit). Getting to working temperature faster is important for fuel efficiency, lower emissions, better flow of oil within the engine, faster "time to heat" for the heater, etc. If the thermostat is not allowing the engine to reach, and stay, at designed operating temperature, the auxiliary fan will not turn as well; since it’s activated by the engine reaching a certain temperature. I would recommend a Thermostat Replacement service which would be performed by a certified technician from YourMechanic. This will allow the confirmation of a diagnosis, and to give you a better idea for repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Coolant Temperature Gauge

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Engine cooling fan isn't working. Steam and liquid is coming out of a black pipe in front of the engine and temperature gauge spiked to H

Hey there. If the engine electric cooling fan is not turning on, the reason has to be determined. The fault could be due to a bad electric motor, a bad coolant temperature sensor, a failed relay, or even a wiring/fuse...

Q: Need problem associated with EPC and ABS Lights fixed.

The EPC Light is for the electronic throttle body. You need to have a qualified technician check the codes on the computer to determine the problem. You may just have a loose vacuum hose connected to the intake. The ABS...

Q: Temperature goes into the red zone during slow driving or idling

Hi there. If this occurred right after the work was performed then it is possible that there is air still stuck in the cooling system, but from what you are explaining with the AC, it sounds more like a cooling...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...