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Q: A/c blowing cold air intermittently with warm air

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My car has around 158,000 miles.The air conditioner blows both cool and warm air. What is causing this and what is the solution. Thanks.

A: Hello. If the system continually blows hot ...

Hello. If the system continually blows hot and then cold, this is typically caused by a failing blend door actuator. If it fails, it can allow the temperature door to not hold the right position. It can also be caused by a bad metering valve or a compressor issue.

I typically start by checking the pressures in the AC system just to make sure that the system is functioning as it should. If it is, then I move to the doors under the dash to see if it is one of them not working properly, or if it is a failure in the control unit. If you need to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your AC system and perform any services that are needed.

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