Hi all.
Car is 89 rs w/3.4 L upgrade. The problem is that I only get air movement from defrost position. I have checked for proper vac hose connections and the hoses are good also. Engine makes 20" of vac. I put a vac pump on the vac line (engine side ) that goes to the dash control, and it holds 20" + of vac.Does this mean the control diaphram is still good? I ordered a new one for it today,just incase.

When the car is running, I cannot hear any leaks at the heat controls. When I have the control on vent, the vent door is still closed.When I open the door by hand, I get a vac hiss,which I think is coming from the vac controller for the vent door.

I checked the check valve off the back of the plenium,and found it was plugged with dried mud( line going to cruise ).Cruise has never worked,either. I put new valve in, and still have no cruise or hvac control.......

What am I overlooking with the hvac?
I have no noticeable vac leaks. I even checked the "orb of power" with the vac pump, and it holds vac....

Thanks !

 

Turned out that the Y connector at the control valve is plugged up with sand, not mud that I previously thought.

I got the "y" bypassed for now,by running a good length of vac hose through the fender, and had to cut the pink hose to splice into the valve. At least I have control function again

Cruise is still not working. I found another pile of sand in the cruise control base as well.Cleaned it out, but cant say that its functional yet. Initial road test tells me no

I'am starting to think that the previous owner cooked the engine rings by running with the orb of power unhooked.When I got the car,the vac hose was dangling in the wind,sucking up who knows what for who knows how long.