O.k., I have pulled the panel on top of the dash out, the glove box out, and replaced all of the check valves and connectors under the hood. But still, once I hit max a/c the air comes out of the defrost vents. I took the actuator for the door to the defrost out and it will actuate when I manually vacuum it. This thing about has me ready to pull the rest of my hair out. Where the line goes through the firewall, is there a check valve there or is it hooked to the metal box below the blower motor housing? Still, if it sits in the heat all day, it will come out of nowhere but the defrost vents for a little while. I can manually pull the actuator down and the air comes out of the dash vents. Please help guys!!!!!!
Thanks,
Michael