So I am having some weird gauge issues on my '88 E250. First, I noticed my oil pressure was acting weird. It would read normal, then would drop way down and just barely be in the normal range, then would jump back up and be where it usually runs. I figured it was the sender, so I replaced it. Seemed to fix the issue for about a week. Then it started doing it again.

I had fixed both the fuel senders in my tanks. They work correctly, but every once in a while when the fuel is sloshing around and the tank is pretty full the gauge will peg past full briefly and then come back to normal (pegs when grounded).

This had all been happening independent of each other and then today I was out cruising for quite sometime at about 35mph.thanks to the snow, and all of a sudden my Oil Pressure, Fuel Gauge and Temp Gauge shoot up. Fuel pegs past full, Oil Pressure jumps up to almost the top of the normal range and Coolant Temp jumps to the top of the normal range. I know that at least the coolant temp was wrong since my aftermarket gauge was sitting exactly where it always does. After about 1 minute all the gauges settled back to normal.

This leads me to believe that it is all some kind of grounding issue, but I am not sure where to start looking. I will be installing an aftermarket Oil Pressure gauge to make sure, but I am pretty sure the stock gauge isn't reading right. Any ideas?

 

The ground that goes from the firewall to the block messes with the gauges

 

Thanks. I will check it out. I am hoping it is causing my issue.