I have a 2001 frontier crewcab and I have noticed an odd heater problem. The engine will get hot and start to blow heat from the heater vents as it should in the winter. When I come to a stop, within 10 seconds, the warm heater air gets cold and stays cold until I start moving again. The heater fan is running, the engine temp is fine and the heater core is not leaking. I am looking for any input anyone might have.
Thanks,
Joel