Not really sure where I should have posted this but oh well. I'm just trying to figure out why when I turn on my A/C that the air only comes out of vents in the top of my dash pad. It doesn't come out of any of the other adjustible vents in the dash itself or from the lower vents in the radio pod. Can someone please help? Thanks. By the way, I just have a regular '86 Firebird.

 

If you still have the brass tree at the back of the intake where all the vacum lines hook up check there. My car was blowing out the floor only, when i checked mine out there was a broke vacum line. Replaced mine and the air went to working fine. Hopes this helps.

 

It does weird things in my car too so I rarely use it. I think it has somthing to do with teh HVAC selector switch. They get old and start to leak. Try what the guy above me said, though.

 

When air only blows out of defroster vent it indicates the following:
HVAC vacumn lines are loose or off the back of controller
Broken or leaking vacumn line where it connects at firewall or at engine(trace line).
Selector(part where vacumn line cluster connects to) is cracked,worn out and leaking.

 

Mine used to do the same thing. Never could figure it out. Then it "fixed itself" after my motor swap, when we also put on all new hoses, belts and ... yep ... vacuum lines. I'd say that was the answer.