I have traced every inch of the gauge harness, specifically foolowing the tach wire, and checked the printed circuit film, connectors, and even replaced the little capacitor written about in another thread.... Still reading crazy high (pegs at idle!) Has anyone tried bypassing the harness and tapping the white wire coming from the distributor, running it directly to the lead on the tach? I know this may be redundant since I just checed the harness thoroughly but maybe this has worked for someone else? I'm about to just make replacement factory-style tachs, maybe with a carbon fiber face!

 

Have you by chance removed the instrument cluster recently without disconnecting the battery first. I did that some time back and my tach gage pegged out after I re-installed it and turned the key. I had to disconnect the battery and manually re-set the tach. It still reads a little high but I can live with it being about 25 rpms high.

 

Oh, I'm sure I had the battery still connected in at leastone of the half-dozen or so times I've had to remove my gauge cluster. It reads 4K at idle but climbs revs far too quick to be just out of phase. Thinking about it, you're probably right about the the battery gig.

I'm thinking it's hopelessly damaged now! I'm coming up with a solution that I think everyone here will love...
Thanks for the input, Trickster. You're always there for us with good advice!
:hail: :hail:

 

Hi
I just bought an 86 iroc
and the whole guage system isnt working
I looked at the fuse and it was blown
I put another fuse in and it blew after driving about 5 minutes.

Anybody think it could be a bad ground?

Dave