I have replaced the radiator, water pump, thermostat, and flushed the heater core multiple times. After changing every part, the heat would work for a while, then blow cool again. The water pump was the most recent part changed, in the past week. I had great heat, but now, nothing. I don't want to keep "experimenting" with this thing. I need an ultimate fix!
My car has 165000 miles.
My car has an automatic transmission.
Hi There, It sounds like you may have a heater core that may have a layer of corrosion caked on the outer linings of the heater core creating an insulating effect on the warm coolant flowing through the heater core. It is possible to get good flow through the heater core while having the inside walls corroded or clogged slightly. This may explain the momentary warm air followed by it cooling down again. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your car’s heating system.
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