i have a 85 caprice classic 305 with ac (not currently connected-bad ac pump). The lever to controll the AC max norm vent heat defrost doesnt control anything. Only thing it controls is off. I did a little fiddling around with the vacuum contection behind the climate control panel and discovered that there is a black rubber vacuum router. If i turned the rubber thing the vents would change but the lever isnt controlling that. Any suggestions?

Check the vacuum line from the firewall to the engine for damage. The line should be on one of the rear vacuum fittings on the carb or on the intake.

i have a 85 caprice classic 305 with ac (not currently connected-bad ac pump). The lever to controll the AC max norm vent heat defrost doesnt control anything. Only thing it controls is off. I did a little fiddling around with the vacuum contection behind the climate control panel and discovered that there is a black rubber vacuum router. If i turned the rubber thing the vents would change but the lever isnt controlling that. Any suggestions?

the vacuum is coming from the vacuum ball in the engine compartment these lines are prone to failure most likely cracked...this controls the vents/hot cold door...

Does anyone know where to find a diagram or schematics of the vent control sytem in the caprice... I have similar problems with my vent controls. I ran a new vacuum line from the vacuum ball to the vacuum swithch thing and the switch still doesn't change anything... I think that it is sucking air from outside instead of recirculating cabin air... I would like to know where the door is to change this setting if there is one at all. The compressor is newish, the freon is good and a new dryer... but the car never cools down as it should - plus compressor stays running continuously all the time when engaged... is this normal?

I figured out my problem. The gear that the is on the end of the lever that controls the other ring gear that is connected to the vacuum direction broke off. Sunbound take your dash control off and look for the gear for the vent controller. That was my problem, still dont know how to reattach the ring gear so it keeps a vacuum though.