Skip the auto shop - Our mechanics make house calls

Q: What's makes the temperature hand goes up then down?

asked by on

The temperature hand goes up to normal then goes to cold. The heater starts out warm then blows cold air.

My car has 150000 miles.
My car has a manual transmission.

A: If you are referring to the engine coolant ...

If you are referring to the engine coolant temperature gauge on the instrument panel, unless the gauge is misreporting the temperature, a likely cause of too low of an engine temperature is a cooling system thermostat that is stuck in the full open position. If the thermostat is stuck open and the coolant is too low in temperature that would account for the inadequate heat in the cabin. There is also a heater control valve which you want to check and see if it is fully open, that is allowing hot engine coolant to enter the heater core (little radiator) in the passenger compartment. If you wish to schedule a heater is not working diagnostic please contact YourMechanic and they will dispatch a certified professional to assist you.

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・Save up to 30%

Get a quote

What others are asking

Q: Timing belt broken and car does not start - 1996 Mazda B2500

According to Gates, a leading manufacturer of timing belts, your 2.3 liter engine is a non-interference engine. This means that a timing belt failure as you describe should not cause the valves to strike the pistons causing serious damage. However,...

Q: What type of oil do I use in my altima

That's a good question. I did some research and it says 0W20. However, there is a small chance that my information is incorrect. Most vehicles, especially new ones, you can find the oil type on the oil fill cap. It...

Q: Ac compressor. Blowing hot air through front vents and cold air through rear vents.

It sounds to me like you have a blend door actuator problem. The blend door actuator is responsible for controlling the blend door. The blend door is responsible for blocking off air to the heater core when your air conditioning...

Related articles

How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.