C3 electical problems? (1978)

[David B.]

1. At times, mostly in cold weather, my tachometer does not work until the car has warmed up after 5 or so minutes of driving. What is the most likely cause of this?

2. Again, only at times, the power window on the drivers side will not work. Any suggestions?

DB

[Tom R.]

Re: C3 electical problems? (1978)

I noticed your post on Friday adn waited to see if anyone would respond...and they may. My first response was that I probably wouldn't work real well in the cold either after so many years. I'm in the South now and both me and my vettes love it which fails to address your concerns.

I'm only speculating but if the systems work well once it warms, it may be that the lubricates have stiffened over the years and the power doesn't have the capacity to work through the "calcified" lubicrants. Perhaps, just doing an overhaul with new lubicrants would work.

I suggest this because my passenger side lock mechanism froze up and I couldn't get the door open. Once I finally did and got inside the door panel, some WD40 made it all better again and immediately. I proceeded and took the linkages apart cleaned and relubricated. It works smoothly now.

The same may work for you without having to invest dollars in new parts.

[Greg A.]

Re: C3 electical problems? (1978)

I too suffered intermitent tach issues with my '78. Replacing the tach filter cured the problems.

As for the window, I suggest you pull the door panel and completly clean and re-lube the window mechanism (probably do both windows.) If that doesn't help smooth the operation, you'll note that the electrical connector on the inside of the door panel has a bit of an odd mounting orientation. If the door panel has been off and on a lot, it's possible the connections may be loose. I had to re-solder all the connections on my driver's door to get consistent operation.

Good Luck.

Greg.