Skip the auto shop - Our mechanics make house calls

Q: thermostat?

asked by on

the temperature gauge goes up to the middle (straight up) once the car heats, then once I turn the fan on for the heat it backs down to the left and stops halfway between 100 and 210. Is this normal or does the thermostat need to be replaced?

My car has 213000 miles.
My car has an automatic transmission.

A: It is not uncommon for the temperature gaug...

It is not uncommon for the temperature gauge to drop when the heater is switched on, especially in colder situations (below 40 degrees f). The thermostat should be able to control the engine temperature in a way that you should be able to still get hot air into the cabin when the heater is engaged. I usually suggest that as long as the heat coming into the cabin is sufficient to keep you warm, I wouldn’t normally worry about the lower temperature on the gauge. If the air coming out of the vents isn’t getting warm enough though, I would try changing the thermostat. If this is something that still worries you, and you feel that you could use a hand in diagnosing or repairing it, I would suggest consulting a certified mechanic, like those available at YourMechanic.com.

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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: How do I break in my new car?

If you purchased your car new, there are a few driving strategies that you should employ to help break your car in: For the first 200 miles of driving, you should try to avoid hard stops. For...

Q: Difficulty starting

Hello there: If you're having difficulty starting your 97 Honda when it's extremely cold outside, it's usually due to fuel not being inside the fuel injectors. When it gets really cold outside, fuel will return to the tank; causing the...

Q: Heat Defroster Not Functioning Correctly

The smell and fogged windows is an indication you are leaking coolant out of the heater core in the dash heater. You should check the engine coolant level to see if it is low indicating the leak. If system is...

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...