What causes overheating when there is circulation on a Chevy Malibu?

Answer 1

This could be from a number of different reasons. thermostat could be bad. cooling fans might not be kicking on. radiator could be clogged up. could be an airlock in your coolant lines. pressure cap could be bad on your overflow tank(enclosed radiators only). thermostat is easy to replace. if the cooling fans arent working try turning your heater on to see if they come on when operating the heater. If they work its most likely your pcm sensor which they run off. that's a costly fix. unclogging your radiator is simple as dissconnecting your lower radiator hose and flushing it out with a garden hose and fresh water. if an airlock, right behind the thermostat is the coolant bleeder valve (looks like a screw in a screw) just loosen it till it looks like a small stream and pour antifreeze in your coolant tank till no more bubbles appear. to check your pressure cap...there is a very small peice of metal on the inside of the cap. many times they get old and rusted (because coolant turns acidic after time) if this is the case its as simple as paying ten dollars for a new cap but make sure you have the right psi. should be 15.