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Q: Running hot

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I just had the thermostat and radiator changed out. I put the correct fluid inside. As I take off, it starts running hot. It really start running hot when I press the button for AC or heat

My car has 204469 miles.

Overheating can also be caused by a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.

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