Sitting at idle, I heard a buzzer sound... It went away so I looked at the gauges to see what was wrong, everything looked normal. A few min
later I looked down at my oil pressure gauge and it was pegged past 110. I shut the car off and restarted it. It was back to normal so I went for a ride... As I was doing 45, the oil pressure gauge was slowly going up and down from 60 to 110... At 55 it stayed around 110.
Can anybody help???? Thanks

 

1. Buy a 142 ohm resistor and attach it to the end of the wire that fits on the oil sender unit. Then attach the other end to ground. Turn the key on and the oil gauge should read approx 60psi. That should give you an idea whether or not its the gauge or the sending unit.
2. If you don't like the above buy a SunPro mechanical oil pressure gauge (very cheap) and install it where the present sending unit is. Then yoo will know what your real oil pressure is.
3. Hopefully you have already made sure that the connector on the sending unit is on good and there are no bare spots on the wiring shorting the signal. Step three here is where your real problem is.