Skip the auto shop - Our mechanics make house calls

Q: What would cause the temperature gauge to go cold to hot then back to cold

asked by on

When driving the car the temperature gage goes to normal temp then to cold then back to normal or hot an this continues happens when you are driving it

My car has 1300000 miles.
My car has an automatic transmission.

A: The engine temperature is regulated by the ...

The engine temperature is regulated by the thermostat opening and closing to maintain the engine temperature. The cooling fan clutch also will maintain the engine temperature to keep a controlled air flow across the radiator to maintain the engine temperature. In order to test the system you will need to monitor the coolant temperature and the operation of the cooling fan clutch to see if the clutch is staying engaged too long causing the cooling system to get too low before the fan clutch disengages. Replace the cooling fan clutch if clutch operation is erratic. Replace the thermostat if the thermostat lets engine temperature get above 200 degrees F before it opens fully. The thermostat should maintain the engine temperature at about 180 degrees F.

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

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: Car overheats while idling

It sounds like you may have a problem with rust an scale build up in the engine. This build up may have worn the impeller on the water pump and this is why it only overheats at low engine RPMs....

Q: Car runs for 5 miles and loses power. 1998 Lincoln Navigator

Hello - first task is to read the problem codes that are turning on the Check Engine light. If the engine is really overheating, the problem could be a stuck closed thermostat, or a blown head gasket. It is also...

Q: Where is the Crankshaft Position Indicator on a 1998 Infiniti QX4?

The crankshaft position sensor is typically externally mounted on the engine near the crankshaft pulley. I would recommend checking near the crankshaft pulley for this answer. If you need help with the replacement of the crankshaft position sensor, I recommend...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...