c3corvettes

I had a similar problem once upon a time in my '80. The fuel needle would fluctuate a lot also. I came across a book titled "Corvette Weekend Projects" and it recommended to check for the grounding wire at the starter motor and to make sure that it is grounded. I had a lot of weird electrical issues at the time. I looked under there and sure enough there was a black ground wire hooked up to the selenoid or I think battery power not sure (I can't remember it's been a while), but when I relocated it to one of the starter to block bolts, all of my electrical gremlins disappeared. I found it interesting that the book specifically covered that ground wire. It mentioned that sometimes people forget to reconnect that ground wire or they simply connect it to power. Just my 2 cents.

Good luck with it

7T1vette

If the meter needle is really "jumping around" and not just 'floating' a bit, the ground wire could be broken internally (or at the connector) and just making intermittant contact. And, if that's what is happening, it would be a real PITA to watch on the console.