OK guys this one got me stumped. Here is the deal, 2000 Z28 and the heater/AC will only blow on def and floor. I have 3 other cars to compare notes to and all looks good between all the cars. I am guessing the issue is vacuum, My car and my wife's car has alot of vacuum at the union behind the glove box but RS/SSCamaro's car does not. I cannot find any kinks or pinches in the black hose leading into the interior, I cant hear any leaking anywhere (does not mean there is none), power brakes seem fine and other vacuum items seem to work just fine as well. I have traced the hose to the back of the intake in a VERY difficult place to see or mess with. Any ideas of what can cause this? Any one have schematics to assist me in figuring out where all this stuff is supposed to go? Also I must tell you that this all worked just fine in the 2000 Z28 but once the engine and interrior was moved to the 1996 RS the heater vent controls would not work right. There is vacuum at the controls just not very much.

Massey

 

If there are no vacuum leaks, then the air doors could be stuck or the vacuum actuator that actually moves them could have gone bad. All that stuff is inside the air plenum.

 

OK Doors all move good, if you push them in they will hold in place or return to the closed position very slowly. This is telling me that I dont have enough vacuum. What I was wondering is do any of you have schematics of the vacuum lines in this system? and does any one know of a common place to spring a leak that could be robbing my vacuum pressure.

Massey

 

interested in this as well

 

im not sure if the ls is the same as the lt but this is what i have. could be leaking in the contol valve.