Heater/AC Control problem
 

I just bought my 16 year old son his first car. It's a 1994 Camaro 3.4 5-speed. I just noticed that the heater (or AC) will not blow through the dash vents even when the control knob is in the correct setting. It will only blow out through the floor and defrost vents on top of the dash and never change.

I did read something about a "control valve" but could not find anymore information about it. Not sure if this would be the cause or the panel itself.

Any help would be great!

Thanks!

I have the same problem on my 2000 B4C, blows only through the floor and dash defroster vents. After some searching, I'm almost completely convinced it's that a line has accidentally been disconnected from the back of the intake. It's a small vacuum line on the back of the intake, I just haven't gotten to take the intake off yet to confirm. Good luck!

Mine would do this, but only under engine load. The air would switch from the top vents to the bottom ones until the engine load eased (engine load decreases manifold vacuum). It was the vacuum line as you suspect, which had abraded just below the passenger side headlight where it passes through the chassis. The line runs from the back of the intake, around the passenger side of the engine to the vacuum tank underneath the car, below the battery. Check out Restore Airflow to the Dashboard Vents.