Car runs hotter during higher speeds then cools back down during lower speeds
My car has 1145000 miles.
My car has an automatic transmission.
Hello. If the car is running hot at higher speeds, then that typically means it has a clogged radiator or a thermostat that is not fully opening. It can also be caused by a slightly leaking head gasket. I usually start by doing a block test just to eliminate the head gasket as a possibility. If it is fine, then I use a temperature gun to diagnose the other components in the cooling system. If you need to have this done, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the overheating problem and proceed with appropriate repairs.
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