Q: Heater doesn't work

asked by on December 30, 2016

Hi, my in cabin heat doesn't work well. If I turn the fan off for a minute and turn it back on it will blow hot air for a few seconds and then it will get cold again. The blower works fine, and I just filled up the coolant. Please help! Car doesn't overheat

My car has 100000 miles.
My car has an automatic transmission.

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The heater control valve may not be opening fully and/or the heater core, beneath and within the dash, may be partially plugged. In both cases, the result would be inadequate heated engine coolant flow through the heater core and no heat. I recommend you request a no heat in cabin diagnostic and the responding certified mechanic will first check the heater control valve for free and complete operation. If the valve is admitting coolant to the heater core and you still have no heat, either the core is plugged or there could also be an issue with the blend door not moving to the "full heat" position. In all events, the mechanic will identify the issue for you and let you know of the cost to repair.

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