Skip the auto shop - Our mechanics make house calls

Q: overheating problem

asked by on

I own a Hummer H2 and it continues to overheat. I have replaced the thermostat, the water pump and the heads. But I still am having the overheating problem. What could this be caused from? Do you have any answers?

A: Thanks for writing in about your Hummer H2....

Thanks for writing in about your Hummer H2. Let’s cover the basics of diagnosing a overheating issue. First, verify the actual temperature at the thermostat housing. Cooling system (and cap) has probably been pressure tested by now. If it tends to overheat in stop-and-go traffic, but not at cruising speeds, then it’s an airflow issue.

Check the fan clutch, shrouds in place, and look for debris blocking the condenser/radiator. I don’t know your mileage, but both the belt and tensioner should have been replaced by this time. If it is overheating at cruising speed, the radiator should be checked for restriction in flow. Have this checked in person by a trained mechanic in order to diagnose the overheating issue and move forward with 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

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 shaking when applying brakes and going slow. Check Engine Light is on and engine idles roughly.

It sounds like you may have a vacuum leak on your car. Check all vacuum lines and make sure they are in good condition and connected. If you don't see a leak you can spray some carburetor cleaner on the...

Q: Car wobbles in the rear.

You could have a bent rim or a bent hub. I would have the rim and hub checked to see which one is bent. I would recommend having a mechanic, like the certified ones at YourMechanic, come and check it...

Q: Overheating above 60MPH - 2002 Nissan Frontier

Hello there, many faults that will cause your 2002 Nissan Frontier to overheat above 60mph. When overheating is seen at speeds the most often faults are the radiator, low coolant level, air in the cooling system, or a faulty cooling...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
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.