This is a weird one. I live in AZ so A/C is almost a necissity out here. But my AC only likes to work sometimes. This is what happens, if I start my truck and am at idle and turn my A/C on it works fine. But whenever I go to leave and hit the gas I hear this sound as if a vent is flipping over somehere behind the dash and Heat starts billowing out instead of A/C. If I turn the A/C off and don't touch the gas then trn it back on the A/C starts working again, but the second I have to give it a good amount of pedal I'll hear that flap and Heat starts coming out again. It really annoys me. Any suggestions?

 

Sounds like the blend door is broken. If you change the temp with the ****, does it function properly? Just a thought.

 

Do you mean that:

1) The airlow changes from the dash vents to the floor

or

2) that the temperature of the air flowing from whatever outlet changes from warm to cold to warm.

If 1, then you have a vacuum leak.

If 2, then its a blend door problem.

Steve

 

Thanks for the response. Blend door sounds like thats gonna be it. I'll give a go and let you know if that fixed it

 

prb2, was it the blend door?

I had the exact same problem today. I would get hot air out of the vents with a/c on then turn it off and back on and get cold air for a while the hot again while driving. At one point when I had cold air I move the temp **** all the way to hot and still had cold air.