Q: Car overheating, new water pump, new radiator, head gasket is good. Why is it overheating?

asked by on

Water/ coolant gets to boiling and comes out the reservoir when car starts to over heat, seems like water not circulating
My car has an automatic transmission.

This can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. Depending on the location of the water leak, this may also be the result of a failing water pump. You may notice a slight whining sound due to a loose water pump pulley, steam coming from the radiator (as you described) and the most obvious for most, the engine overheating. I would suggest having an expert from YourMechanic come to your home to diagnose your cooling system.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 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!
  1. Home
  2. Questions
  3. Car overheating, new water pump, new radiator, head gasket is good. Why is it overheating?

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: My car constantly overheats within a couple of minutes and I've had all of the cooling system replaced already.

Hi there. If the engine takes a little time to overheat, then it is possible that the radiator could be plugged up. If the engine overheats fast, then either there is air in the cooling system or one or both...

Q: Car stalls out and has starting issues

Hi there, thanks for writing in. I'd be happy to provide some insight. This sounds like potentially a bad grounding problem. Try checking the black battery cable to be sure it is properly connected (opposite end of the battery) to...

Q: My car needs a new water pump but what else should be replaced?

If the car is overheating or the rate of coolant loss is so high that it will likely overheat, you should not drive it because overheating will damage the engine. The most common related services accompanying water pump replacement are...

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...
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...
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...