Skip the auto shop - Our mechanics make house calls

Q: My car is overheating and I would like to pinpoint the cause.

asked by on

I purchased this g35 recently so I don't now much about the prior history but what I do know is that it's now starting to overheat. First indication that something may be wrong with my cooling system was one night when trying to warm myself up inside my car I noticed that there was no heat. This was the first time I needed heat so I don't know if this was a new problem or old. I opened up the radiator made sure there was fluid present and tried burping it with the relief valve, no change. Next day while driving to work I noticed the temperature kept rising. Pulled over, waited for it to cool down, put water that I had near me in there. Temperature seemed fine. Couple days later same problem except this time it was not sovled. Thought it may be my thermostat. Changed it still no change. Now I am thinking it may be my water pump but I haven't noticed any leaks and the oil doesn't seem to be mixed with any coolant (as far as I can tell) and my radiator seem to be working just fine. Thanks

My car has 105000 miles.
My car has an automatic transmission.

A: Great description of the problem - your obs...

Great description of the problem - your observations helped eliminate the issues it could possibly have. From what you’ve described, you may have a clogged heater core. Fix and flush your system. While flushing the system, make sure you look at the color of the antifreeze and see if you notice different colors. If so, then there is your problem.

You made a suggestion about the water pump. This could also be the cause, but I would try more simple solutions first and see if you can get it back to proper running temperature.

Note: A cracked head gasket doesn’t always give you signs like milky oil or oil in your antifreeze.

If you would like a more precise diagnosis of the issue, a certified professional from YourMechanic can come to your location to inspect the overheating problem and follow through 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

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: Serpentine belt came off of 2004 Lexus IS 300

Hi. The timing has a service life of 90,000 miles. Depending on the vehicle's mileage and the last time the timing belt was changed, it will determine when you need to have it replaced. The water pump itself has no...

Q: Radiator keeps blowing coolant back into holding tank

Hi, thanks for writing in. This is a sign that you may need to have the radiator system burped. This is a process that is used to relieve the air in the system which can cause the coolant to overflow...

Q: Car overheating; thermostat

Hello! A common reason for most vehicles to overheat is a faulty thermostat. However, on 350Z's, the factory fans are known to fail prematurely and cause an overheating scenario. I suggest checking the performance of the cooling fans and thermostat....

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...
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...
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...