Topic: Vacuum Leak
in Forum: C3 Cooling and Heating Systems
Where is the best place to start looking for a vacuum leak that affects the heater and defroster door from changing? Once in awhile I can get the defroster to blow on the windshield, but mostly it blows on the floor and I just noticed today that I hear a vacuum sound through the defroster vent when it's on heat. The sound goes away when put on vent or defrost. What a time to start acting up, just when it starts to get cold. Thanks, Tom




I have the same defroster problem with my '82. I've checked everything except the diaphragm, which I am sure is the culprit. I can hear a return spring over-riding the initial vacuum to the diaphragm and slowly the defroster turns to a heater. I haven't fixed mine yet either, but this year for sure. Don't give up, these fine cars need a lot of TLC, but they are worth it.
terntes