I have a 1990 IROC-Z and as with many of these cars, the tach does not work properly. It is operated by some sort of IC board, which is no longer available.

I happened to have the instrument cluster from a 1991 V-8 RS Camaro donated to me, and I noticed that the tach does not appear to use this IC board?

Does anyone have an original GM 1992 Camaro service manual? I would like to see if the tach wiring really is different by seeing the tach wiring diagram. I sure would like to get my tach working properly again.

Thanks, Andy