Check to make sure that the wires on the ammeter is tight. I had a weird situation like that on my truck. I'd fire the careless guy who didn't tighten that nut, but I'm a one man show.
Check for loose connections elsewhere while you're at it.

Last edited by 52Carl; 09/16/2020 1:33 AM.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission