Heater/AC Control or NO-Control

When I turn my AC or Heater on I have no control over where the air comes out. No matter if I select defrost, foot or in the face air it comes out each area. The fan increase/decrease work OK. Has anyone experienced this and if so, how did you get it fixed. Thanks.

[c4c5specialist]

HI there,
You are probably having a vacuum leakage, near the vacuum source tank.
If you reference the diagram attached to this post, you will see the tank, hoses, and check valves, as it is positioned directly behind the PCM and the TAC module.
I would suggest that you have had some battery leakage, which ate the vacuum harness, causing your loss of modes in your HVAC.
Please let us know if you need further help.
Allthebest, c4c5

Thanks. I will definately give it a look this weekend. As you said, it may have had a battery leak before I bought it. Will let you know the outcome. Thanks again.

Jefe,
Yeah, I'm having the same problem with mine right now. I have a tread going myself. I only place my air will come out is the heater and defrost vents, not from the A/C vents. I am going to be searching for this same vacum leak myself this weekend.
rich95

[danl72]

I had the same problem and took my Vette to the dealer and the problem was solved. It was a vaccum hose leak. Now everything works just great.