Q: Heater is not working when I turn heat up and on.

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I turn my car on and put the heater on and cold air blows out. I've changed the blend door actuator, fuses, and checked the coolant levels which were all good. I also checked the two hoses that go to the heater core to see if the heater core might be clogged but both hoses still get very hot. Would you recommend me still flush out the heater core in case of it being clogged?

My car has 163000 miles.
My car has an automatic transmission.

This may be due to a clogged heater core. As you 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. If the hoses running to the heater core still get hot, this may suggest a backup inside the heater core itself. I would recommend having an expert from YourMechanic come to your location to diagnose and repair your heater core.

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