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Q: AC Blowing from vents and defrost

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When I have the control knob for AC on front vents it blows out of all the vents including defrost. If I have the knob set to defrost the air only comes out of the defrost vents. What could be causing this issue?

My car has 70150 miles.
My car has an automatic transmission.

The air conditioner blend door is controlled by an electronic actuator and if the door is not in set position then you may have a defective actuator and need to replace it. The door operation should be in the manual mode to make sure the actuator is defective or there is a blend door stuck from something getting down in vent door. Sometimes a pen, paper clip, or pencil can fall in the defroster vent and can lodge in the door and not let it seal. If this is the case, then the evaporator case may need removed to get out the item out of the case door. I would have a professional scope out your AC system firsthand and determine what fixes will help.

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