Temp gauge issue

[jthompson]

The problem I am having is that when I crank the jeep the temp gauge, oil pressure gauge, and the voltage gauge bounce back and forth. What could be causing this issue? Thanks.

 

[Torxhead]

O.K. so how did all this start? I think the only thing they have in common would be the ground.

 

[jthompson]

Well the temp gauge wasn't working so I out a new sensor in and a new gauge and that's when I started. The oil pressure and voltage gauges didn't start this until I put the new temp gauge in. I have the cluster just hanging with the new temp gauge hooked up to see if it worked before I put it all back together since its a pain in the butt. Could this be causing the problem?

 

[Torxhead]

The temp and fuel level gauges are tied in together and must me replaced together, or so that is what I have been hearing all these years. Oil pressure and voltage gauges are on separate circuts unless somebody made some changes. You could disconnect the oil pressure and voltage gauges and go from there. A wiring diagram would be good here to trace down any miswiring that was done. The big box 4wd outfits can get you any replacement parts if you need them. You don't have what year CJ it is posted, so I am assuming it would be a later model with the instrument cluster.

 

[jthompson]

It's a 1978. I will try replacing both gauges and go from there