1999 Ford Explorer Q&A

1999 Ford Explorer Question: Heater blows cold air

Heater blows cold air and after 20 miles or so it will start getting warm. It then starts blowing cold again. It goes back and forth like this while running. -
Answer 1
Sounds like a classic thermostat issue. However, if the engine is hot enough, it could be a temperature blend issue inside the dash. -
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