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Q: Heat control blows hot then cold air

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Heat control blowing warm then cold air. While on heat.

My car has 4300 miles.
My car has an automatic transmission.

A: This may be due to a bad heater core. As yo...

This may be due to a bad heater core. As you may know, the heater core is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to heat the inside of the car with the help of the blower motor that blows the warm air through the vents inside the car. I would recommend having an expert from YourMechanic come to your location to diagnose and repair your heater core.

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