Shoehorn

I have been looking at a number of 78-82 Vette's and I have came across about 1/2 of the 15 cars I have looked at having "problems" with the defrost not working or not working properly or weakly. I also saw this issue on one vehicle here on this site that I was veiwing for possible purchase and it had the same problem. My questions is, is this a common issue? Can it be fixed cheaply or not? Or have I had the ill luck in becoming a beacon for Vette's with defrost demons... :crazy:

79 Midnight Blue L82

Very common problem. It's in the vacuum system somewhere. Never have got mine sorted out yet and generally just get ticked off everytime I mess with it.

I'm about ready to contact the good Dr. Rebuild and get a new set of vacuum lines and that would pretty much force me to run it all down and solve the problem.

:banghead:

MELVIN

I would suspect the control switch first. The doors are actuated by vacum. The switch that is pulled from side to side that closes or opens doors have a small, perforated diaphram inside the back, that allows or shuts off vacum to the various hoses that are attached to the back. This diaphram is usually the first to go. I have changed a few in both vettes and other GM's from 78-81 models. You dont have to replace the whole switch. Only the small part that has the diaphram that is located in the back. If you dont have a good parts manual, go to any GM dealer. Have him get the exploded view of the area we are speaking of, and you will see it. Pretty easy fix, and the part is commonly available

joeveto

I know I am beating a lot to the punch with this comment, but....

I have found a lot of things to not work on these cars, and yes, it's very common. :lolg: :sad:

That's why it's a hobby. A neverending hobby.

Jack71

:lol: :lol: :iagree:

Shoehorn

Never-ending as this hobby may be, I would like to find out which aspects of this hobby are more common/expensive vs. common/cheap...... :D

Crash80

Most seem to be the former!