71 Cutlass Supreme

When I move the a/c control lever the air doesn't change to the vents or defrost.

Originally an A/C car but it has been removed.

Thanks. TP

 

Sounds like a vacuum issue. IIRC when I did my heater core on my A/C car. When installing the heater plenum, I pinched one of the vacuum hoses between the firewall and plenum, no change in air direction when selector lever was changed. Easy fix for me.

Do you get a hiss when changing positions with the selector lever?

Pat

 

The controls are vacuum operated, so even with the A/C removed, you still need the vacuum lines and canister connected properly. I'm guessing all that got ripped out indiscriminately with the A/C.

 

Hmmm - yes I do get a hiss.

There is a vacuum line coming off the intake manifold towards the passenger rear. Its connected to some kind of valve thing. Not sure how to describe that. What should that be connected to? I'll probably have pull out my after market stereo, etc. to get to the A/C panel. Which will be a pain.

Also - There is this plastic assembly in the passenger kick panel that had a vacuum house attached. It had cracked at some point of the reassembly. I just put duct tape on it to fix.

Lastly, there is a square (approx 2 inch) hose on the passenger side that is disconnected. I thought it went up to the passenger vent, which I don't really care too much about as I never sit there.

Thanks as always.....TP

 

I think we really need pics to help. The short explanation is...the vacuum comes from the intake manifold through about a 3/8" rubber hose and goes into to a plastic cannister that mounts on the firewall. Then it comes out of the cannister in a very small hose like 1/4" or less and goes thru the firewall and gets split 6 ways to Sunday. There is a vacuum servo in the pass vent panel. That has to be good for anything to work. You can't fix it with duct tape, if that's cracked it has to be replaced. I would not use a used one, new it's about 60.00. The big 2" hose is not really the prob, or an issue at this point. Hissing means it's leaking some place. You have to check the connections under the hood to start.

 

Well. There we go so there are two problems. There is no black canister on the firewall. It's in a box on my shelf. And the cracked vacuum thing. Bet if I address those issues all will be well. :-)