car is overheating when driven ok @ idle
i would check waterpump,theromastat,rad,cap also check oil if milkey looking,blown head gasket.
Agreed. The engine is under increased heat when driving due to more workload on engine. So, if the water pump is not cycling properly, or there is another problem, it will overheat. Head gasket is a likely issue, one way to check this is to uncap the radiator cap with engine cold and run the engine. If there are bubbles or splashing/shooting coolant out, head gasket is blown.
check the belt on the crank make sure its not worn out or that its there lol
if the car is older than 7 yrs, or has alot of miles i would check the thermostat and the water pump. it wouldn't be a bad idea to replace the water pump anyway, with one that has metal fins. the factory pump has plastic fins and they can fall apart and cause future problems.
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