Skip the auto shop - Our mechanics make house calls

Q: After fixing my radiator, radiator hose, thermostat, and idle control valve my car continues to idle very high and run hot. Help??

asked by on

When I crank my car it idles extremely high but I have already changed the control valve. Also, I have changed my radiator, radiator hose, and thermostat all which needed to be changed and my car still runs hot. Any professional suggestions because family members that know about cars and mechanics have all said that it can only be the heater core or the water pump but I don't know which one it is and I am afraid that I'll fix the wrong thing.
My car has an automatic transmission.

Hello, high idle can be represented by many conditions. A heater core would not cause this unless you have a coolant leak and the core was leaking. There are tests that can be performed to test a water pump (coolant pump). A vacuum leak can create high idle and even a high engine temperature. A suggestion is to read engine data and any fault codes in the system. This is done with a scan tool. The scan tool can read data which will give you information on the operating systems of the vehicle. If you’d like, a certified technician from YourMechanic can come to your location and do a complete evaluation of the overheating issues.

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!
  1. Home
  2. Questions
  3. After fixing my radiator, radiator hose, thermostat, and idle control valve my car continues to idle very high and run hot. Help??

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 jerks when driving uphills and accelerating

The problem sounds like a misfire in one or more cylinders when under a load. The fuel system pressure would need to be checked to see if you have the correct amount of fuel pressure to run the car under...

Q: Car is overheating

The cooling fan and thermostat would need to be checked for operation first. Also, the system pressure should be checked and tested for leaks. I recommend having a mechanic, such as one from YourMechanic, come out to you and inspect...

Q: DOES YOURMECHANIC DO CATALYTIC CONVERTER SERVICE JOBS.

Hi Cornelius. Thanks for submitting your question today. It depends on the vehicle and location as to whether we can complete the catalytic converter replacement. I have forwarded your question to our sales and service department, so they can look...

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
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...