89VetteGirl

My 1989 TPI has no A/C right now. I recharged the system and retrofitted it to R134. The compressor runs and the accumulator gets cold, the proper hoses get cold and the proper hoses get hot- everything under the hood indicates that the system is running well. However, when I get into the car, only hot air blows out of the vents- hotter than outside...really hot! When I first turn the car on and put the A/C on right away, it is cold for a minute or two, but gradually gets hotter and hotter. My boyfriend think there is a mode door stuck open to not let it switch between heater and A/C. Can anyone tell me if this is probable, and if so, where the main mode door is? Also, even with all air and heat turned off the car blows hot air off the engine onto my feet. It gets really hot and burns, but I can't seem to get it to stop. Is this related to the A/C problems, or something else? How can I get it to stop?

SunCr

There is a Module (Electronic Air) or Resistor Pod (Manual Air) mounted on the right side of the Evaporator Case. Remove it and look inside to see the Temp Door. Door should move between 60 and 90 or Cold and Hot. If it doesn't, Electronic controls it with an electric motor and it's connected to the door's linkage with a plastic clip that's probably broken. Manual controls it with a cable. Access is from the passenger compartment. Remove the Hush Panel and ECM to observe the motor. Cable should be visible without having to yank the ECM.

89 Bob L

Chances are that the clip to the door motor is broken or disconnected.

89VetteGirl

Thanks to everyone for the help. I opened up the evaporator box and moved the door to cold, and now the A/C works wonderfully! I may have to go change the mode back to hot when the winter comes, but I guess I will have to see. for now, it is good.

pablocruise

That was serious surgery. Was the sticky gasket a PITA?
Did the door move easily or did it take effort to move it?

89VetteGirl

The door was not too difficult to move. My boyfriend did it actually - I wanted to help but he did it in practically a second- so I cannot imagine it was difficult. I have no idea about a sticky gasket, I just know that the A/C works great now. The car gets very cold.
By the way, we switched it over to R134A by using one of those $30 kits found in any auto parts store. It came with the conversion gaskets, hoses and the refrigerant with stop-leak. Good value, but we had to go get a valve cover with the core inside for the high pressure side, because the original core was bent and corroded.