95 z28 Recently swapped engine into another chassis & the oil gauge is pegged (before I did the swap) so I know my engine has good pressure but the gauge was already like this what does that mean? Any input is appreciated

 

Is it possible it's just stock on the gauges faceplate?

 

Could be that was my next guess
I’ll take off the cover & try to reset the gauge & see what happens

 

If it goes that far when you turn the key on (engine off), it would be an open circuit. But when you turn the key to off it would return to 0. If it stays where it is in the picture, it's either stuck or the gauge circuit is shorted to a non-switched 12 volt supply.

 

Ok so I reset the needle to 0 & when I turn the key on it immediately pegged & doesn’t come back down so what’s the next step?

 

Make sure the 1-wire connector is solidly on the sensor:

http://shbox.com/1/op_sensor.jpg

Key on/engine off, connector off the sensor, measure volts between the single tan wire and a good chassis ground. Should have ~12 volts. Then jumper the tan wire to ground, needle should move to "0".

Key off, connector off the sensor, resistance between single pin that tan wire connects to on sensor and engine ground should be 0 - 10 ohms. Start engine. resistance should increase with RPM, maxing at ~80 - 90 ohms at 5,000 RPM.