This isn't exactly Thirdgen-related, but a friend of mine drives a 93 Cavalier with a ton of miles on it-I don't exactly know how many. Anyways, a while ago, we were going for a ride and we noticed that the speedo wasn't registering any speed. Then we stopped at a four-way stoplight, and the speedo climberd up to 100+ MPH. After driving a few miles, it went back down to normal. I thought that it might be caused by a slight water seepage into the cable or something. Is there anything that could cause this in my Thirdgen?

 

What year, engine etc. 90 and up used an electronic speedo, under 90 it was cable driven. A cable won't do that either way. On a cable unit if it sticks the speedo head is bad. Electronic units are a whole different ballgame.

 

My speedo in my 87 Firebird V6 is not cable driven- there is no cable going right straight to the back of the speedo. I know- I have removed the cluster several times-there is only the two main computer driven connectors that have like thirty or so cables attached to them.

 

Did the birds get them in 87 for the first year? i know the maros didn't get them till like 90-91.....sucks for me...300$ to get an electrical speedo to run with a t56

 

Then it's electronic. Yes, the bird's had electronic first.