Air Conditioning problem
1997 Chevy Lumina 6 cyl Front Wheel Drive Automatic 171000 miles
About a year ago our 1997 Lumina's heating and air conditioning air flow from the vents stopped flowing like it is supposed to. When accelerating or going uphill the air flow stops coming out of the front vents and starts coming out of the defrost vents and the floor at the same time. I am suspecting that either a vacuum or electric actuator is bad. Or that maybe a plastic damper door in the duct work that directs airflow has slipped, come loose, or just plain broke. But before I took the car apart, I wanted to ask the 2carpros. Any help in pointing me in a direction would be greatley appreciated!
Find the vacuum line that comes out of the firewall, this is the supply line, and it goes to a small reserve tank in the engine compartment or under the das, then anothe line goes from the tank to a check valve, then to manifold. If the reserve tank cracks, or the supply line breaks, air will divert to the defrost vents when accelerating. The reserve tank supplies needed vacuum to A/C system during these times!