When I hit my brakes, The oil pressure gauge moves up about an 1/8 of an inch and when I take my foot off, it goes back to where it was.
Last week I had the brakes bled, new spark plugs, Coil and, wires installed but I dont remember seeing it happen after that was done.

The same day I noticed it, I had removed and cleaned up the positive post and connector on the battery.

The other gauges work fine.
I do have a pretty bad oil leak from the pan gasket if that matters.

Should I worry about this or just consider it one of those harmless gremlins that show up time to time?

 

I don't know if the OPG is connected in with the ecm on your van but on my 88, its ground originates from the engine block, through the oil pressure sendor, and directly to the gauge. Maybe you could use a meter and check the ground to the sending unit body and the positive on the battery while someone presses the brakes. That would eliminate a ground issue through the engine block to the sendor.

I don't know if your 94 uses a IVR.

 

The other day I realized the oil pressure gauge also slightly moves up when I have the blinkers on and the hazard lights. Clearly there is some kind of electrical issue.

Thanks for the tip annaleigh.

 

I would think it might be in the grounding somewhere. Seems to me like if it was grounding at the instrument cluster, you would have other symptoms too.

Have you checked the actual connection at the sending unit?
BTW motorcraft SW2220 Oreilly clams to have them fro about the same price as ordering online.

Though it is always a good idea to connect a actual mechanical oil pressure gauge just to check, don't think that would apply in this case as there is nothing I know of electrically that would cause the actual pressure to mechanically drop.

Now my oil pressure dropped a full letter on the gauge once warmed up after I had the oil changed at a shop running a special. I normally run 10w-40 here in the south and they put in 5w-30. That would be reason for me to mechanically check the pressure though i believe it is really just the thinner oil.

Besides the ground, the only other think i could think of would be on the power side. You would need to pull out the instrument cluster and visually check it for a bad connection as well as with a meter. if you don't see anything physically wrong, try disconnecting the sending unit and check the power side of the gauge for voltage with a meter as you press the brake peddle or have the turn signals on.

 

I have not done anything to it yet because its my DD and the electrical gauge is not showing anything out of the norm. When I get time I am going to go ahead and check it out.
Thanks anna.