Hi..hope I am posting in the right spot. I have a 91 Z28..completely stock and original. Lately the speedometer/odeometer/trip odeometer occasionally stops working. Then if you turn off car, restart sometimes it will work for awhile and then stop again. Sometimes the speedometer needle just bounces around. I read that if it was the VSS the cruise wouldnt work well that works just fine. Other than the VSS (and is that the right way to tell if working by using the cruise control) is it the gauge cluster that went bad most likely? Can those be fixed or do you have to replace?

Thanks for you thoughts/help in advance. Dan

 

 

Unfortunately I don't have the answer to your question, but I thought I would share my experience. I too have a 1991 Z28 all original 30k miles. Two years ago my speedometer and odometer stopped working. I haven't driven it since. I did replace the VSS and I was disapointed to find that this was not my problem. I haven't tried anything else, too afraid that I'll mess things up more. Haven't found any real useful information either.

 

If you have a scanner or know someone who has a scanner, you can check vehicle speed to see if the VSS is working properly when the speedometer is acting up. Actually, your check engine light should come on and a speed sensor code 23(i think) for the car being in gear and a high RPM with no MPH if it's the speed sensor. You may even be able to go to a shop and they may hook up the scanner and test drive for a nominal charge. That would be the first easy thing with no disassembly.