Thought i would throw this out there to see if anyone else may have encountered this problem. After 15 months in the body shop and all the dust that goes with it, I encountered a few electrical glitches. I corrected 99% of them by removing the ecu and cleaning contacts and plug. However the problem with the oil pressure gauge remains. Gauge seems to operate correctly after warm up. Whenever I hit the gas pedal the gauge dumps to zero then returns to normal as soon as I release it. I have extra gauge cluster to replace it with , but thought I,d ask if anyone had any other ideas before i remove the dash.

Do you have any other odd electrical symptoms such as other gauges dropping or lights dimming when you hit the gas pedal? Does your tachometer respond correctly?

As for removing the gauge, you can do that by removing the glovebox and heater panel. You can then remove the screws and pull the gauges out through the opening left by the glovebox.

All other gauges working properly including tachometer. Lights don't dim when I hit the gas. The oil pressure gauge works after car warms up, then malfunctions when I hit the gas'

Sounds more like a broken wire or loose connection. Have you looked at the moving parts of your throttle linkage to see if it's moving some wires when you "hit the gas"? There's only two things that should affect the gauge needle - electrical current and oil pressure. Oil pressure would be slow so electrical is most likely. Does it happen if you press the throttle when not moving or only when moving?

Here's a guess - when you accelerate the wiring at the sender swings back and loses connection. It's part of a big bundle. Or the gauge ground itself is losing contact.