Any pics or info on vacuum line for HVAc system? 87 GTA digital dash & push button heat/ac controller...air is only blowing from the defroster...

 

Hi marcus88

I'm chasing the same problem and so far I have found that the vacuum lines run from the passenger side of the intake plenum, next to the distributor. One line runs around the back side of the distributor (next to the firewall) into a "T" connector. From there, one line goes through the firewall somewhere behind the engine, the other goes all the way to the driver side strut tower. It then connects to another "T" connector. The line then goes to the cruse control device and a "vacuum ball" under the battery, behind the fog light.

I find that the rubber hoses are dry rotting and they collapse or break when vacuum pressure is applied. Best thing to do is buy several feet of vacuum tubing from a local auto parts store and replace it all. The sizes are written on the side of the old tubing. You will need 2 different sizes of rubber tubing (i don't remember the exact sizes).

Also, there is hard plastic tubing that runs to the EGR valve and throttle body. These usually break if you move them around too much, so be careful.

 

These diagrams will show which actuators control which doors.

 

And this

 

Sorry, try this.