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 October 09, 2016

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.

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