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Q: AC air switching when I accelerate.

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When I accelerate with the AC on, the air switches from the vents to the defroster vent, and then back to the AC vents when I decelerate. I also need the AC charged. It is cool now, but I think it should be colder.

A: The ford trucks use vacuum switches for the...

The ford trucks use vacuum switches for the defroster. It sounds like you may have a bad vacuum line or a bad vacuum reservoir behind the dash that. I would have a technician, such as one from YourMechanic, come out and test the vacuum system of your AC to see if the air control module is fully functional.

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