The flaps in vent do not flow air in the right positions when tuning knob
www.youtube.com/watch?v=Ow0OOfIFtlU -- sounds like your mode door actuator is not working or the control panel is faulty. Very common on these trucks. Check out this video for some insight into solutions.
I got a 2000 Chevy Cavalier I want to know where at mass airflow sensor is on the car please
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