I've had this problem for a few months now and have tried tricks from people having similar issues as me on this website to no luck.

tachometer works, and speedometer(I assume; car hasnt been driven in years). However, the four gauges in the middle are spotty. The weirdest part of this issue is that the engine temp gauge slowly rises all the way up to Hot from Low upon starting the car. Oil pressure and fuel level do not work at all and battery voltage DOES work.

Ive seen a few recommendations with testing fuse #4 and adding a ground wire, but I messed up the ground and broke my tachometer(now fixed).

My largest concern is the engine temperature because this car has serious overheating issues with age apparently.

Just looking for some direction and any possible threads that may already solve this problem that I havent yet found.

I can send photos if needed.

 

Cleaning all the contacts and adding a new ground is probably the best fix for the gauges.

With overheating, they shouldn't if the cooling system is in good condition. If you haven't been through all of it you should.

 

I would also consider replacing the engine temp sensor. They are not dear and that is the first most likely candidate. Also check the integrity of the connector and insulation on the loom to the sensor.