I HAVE A 1983 T-TYPE 3.8 TURBO AND THE AIR CONDITIONING VENTS QUIT BLOWING OUT AIR THE JUST BLOW OUT THE DEFROST AND THE HEATER PORTS NOT THE VENTS ANY SUGESTIONS
Look for a big round balloon shaped canister near the fan shroud or drivers side fender. It has two vacuum lines attached to it. Track down both vac lines to find if they are broken or disconnected. I had this problem happen to me several times on my '80 Regal and my '81 Regal. Good Luck!