1989 - defroster/vent/heat switch not working

[ron h]

Hi, the switch that redirects the flow of air from the defroster to vent to heat does not work. The air will just come out the top and bottom (blend if you want to call it) no matter where you position the knob on the dash board. I do have front air conditioning only. No rear heater or air. It will start getting cold so I would like to try to get this fixed. The mechanic I took it to can not get the correct part from a dealer. He says that the switch it self and the blower does work. Is this part repairable? Any ideas as to where I can get this part? Thanks for your help.

[rhandwor]

I would call the chevy dealer myself. They may have to order it but they can get it. Otherwise you will have to go to a junk yard.

[Kings-x59]

if I read your last statement correctly, your mechanic says the switch and blower DO work?
if that's the case, it's a vacuum problem. pull the doghouse, way down near the right fender well is a black plastic ball (vacuum chamber), make sure the vacuum hose is connected to this and no splits at the end of the hose.
vacuum hoses control the dampers that redirect air flow in the a/c system ( heating and cooling). You can see if this is working or not.
using a screw driver, on the passenger side, remove the plastic panels under the dash. use a flashlight to find the screws. There's maybe 6 or 8 screws to remove the panels and you can see whether the dampers are opening and closing. cycle through the positions on the switch, the dampers should move, if not it's definately a vacuum problem.

[Kings-x59]

a ford dealer?