AIR COND.
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Intermediate
Joined: Apr 2003
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AIR COND.
HOPEFULLY, SOMEONE CAN SHED A LITTLE LIGHT ON MY PROBLEM!! I HAVE A 1980 COUPE, WHEN I TURN THE A/C ON IT WILL ONLY COME OUT OF THE FLOOR VENTS AND NOT THE DASH VENTS. I THOUGHT IT WAS THE VACCUM VALVE IN THE DASH, PUT ANOTHER ONE IN STILL DOING THE SAME THING. ON THAT VALVE IF YOU PULL THE ARM DOWN AND HOLD IT THE AIR WILL TRANSFER OUT OF THE VENTS, AS SOON AS YOU LET THE ARM GO THE VACCUM PULLS THE ARM BACK IN AND THE AIR JUST BLOWS OUT THE FLOOR VENT AGAIN, :smash: ANY SUGGESTIONS? VETTESALESMAN
Burning Brakes
Joined: Jun 2002
Posts: 792
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From: Norcross GA
Re: AIR COND. (VETTESALESMAN)
When you talk about the valve, I'm assuming you are talking about the actuator on the left side of what I call the air distributor. Do you have vacuum coming to this on at least one of the positions of the selector in the center console. If not, you need to trace back and find out where the vacuum ends. If you have no vacuum you won't get movement.
I had the same problem but had vacuum coming into the multi port vacuum connector on the back of the slider (I don't remember which of the vacuum hoses back there was the supply). I replaced the whole unit and my problem went away.
I had the same problem but had vacuum coming into the multi port vacuum connector on the back of the slider (I don't remember which of the vacuum hoses back there was the supply). I replaced the whole unit and my problem went away.
Le Mans Master
Joined: Sep 2000
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From: Westfield Indiana
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Re: AIR COND. (VETTESALESMAN)
You have a vacuum leak somewhere in the system. Mine was in the main line that goes to the control valve. I used a vac pump to test all of the actuators and I could get it to blow out the dash vents like that and it didn't leak off, so I knew the actuators were good. It took some chasing but I discovered there is a vacuum line that runs parallel to the wipers and is in the engine compartment and that is the main line (on my 79). The hose had come loose somehow. I reattached it and used a zip tie to keep it tight and don't have the problem anymore.
Advanced
Joined: Feb 1999
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From: brownwood, tx
Re: AIR COND. (VETTESALESMAN)
My '80 was doing the same thing. If you move the lever over to the "vent" position, is air coming out of the a/c vents? Mine did this & after it started coming out of the top vents, I could move the lever to the a/c position & the air would continue to blow -- only now it would be cold. After doing this for several days, I found that it started working normal. I guess something was stuck or gummed up & just needed to be operated a few times to loosen it up...Hope this helps.
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Re: AIR COND. (slim)
Thanks for the input Slim, I've tried this, and it just isn't working. I'm probrably going to have to put everthing back together in the dash and start taking apart the console, it might be the control unit itself. Back to the drawing board, as much as I've had this car apart I should be able to troubleshoot this thing in my sleep. :crazy:
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Re: AIR COND. (Captain Morgan)
I know exactly what hose you are talking about, because 2 years ago when I refreshed the engine and tranny I also replaced all of the vaccum hoses with the color keyed kit. Thanks for the reply :)
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Le Mans Master
Joined: Sep 2000
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From: Westfield Indiana
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Re: AIR COND. (VETTESALESMAN)
I know exactly what hose you are talking about, because 2 years ago when I refreshed the engine and tranny I also replaced all of the vaccum hoses with the color keyed kit. Thanks for the reply :)
Burning Brakes
Joined: Jul 2000
Posts: 1,162
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From: Beaverton, OR
Re: AIR COND. (Captain Morgan)
I reattached it and used a zip tie to keep it tight and don't have the problem anymore.
Melting Slicks
Joined: May 2000
Posts: 2,305
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From: Orlando,Fl,USA
Re: AIR COND. (Captain Morgan)
I'm not sure if the 77 is the same but the problem was just as yours. It was the small vac hose from the rubber gromet that goes from out of the firewall behind the distributor towards the pass side. It had a split in the small ridgid white plastic piece that the black vac hose slip on to. It was dangling on just enough to hold the vac line but letting alll the air escape. I cut what was left of it and slid the hose over and presto the top vents kicked in. I hope its that simple for you although it took me some time to locate it. Good luck. BTW I order a hot rod air kit for my car which I hope will be coming soon. It will be a whole new sanden system.
