check the vacuum lines, including the one going to the silver control valve just on the engine side of the firewall - it's on the passenger side kinda between the battery and the rear of the engine. there should be a vac line on the top of it that goes to the vacuum canister in the front pass side above the carbon canister filter behind the pass headlight. could also be vac lines inside the car, behind the dash. you can get to them by pulling off the trim piece below the glove box and by pulling out the radio/climate control units. that's where they go across - it's a tanish/white colored box which has the bellows actuators for the various flapper things tha tcontrol which vents air comes out for the various settings.
if you need more info, let me know and I'll see what i can help you with. if you have manual climate control, then also check the vac lines that go to the "vent" lever on the trim panel below the steering wheel area.