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Q: When the a/c turn on after 20minutes the temperature goes to the red line

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My engine newly top overhaul new head gasket new water pump new radiator new thermostat but still overheating

My car has 250000 miles.

Hi there. Believe it or not, this issue tends to be very common after a major repair has been completed. In most circumstances, the overheating issue is caused by an obstruction in the coolant tubes; either an air bubble or debris from inside the engine block. However, it could be electrical including a relay or wire that was not correctly installed or a ground issue that’s not allowing the thermostat to open. To pinpoint the precise source, I’d recommend having one of our local mechanics from YourMechanic come to your home or office to complete an engine is overheating quickly inspection.

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