[Blackcrow64]

The oil pressure sending unit screws into the bottom of the oil filter housing. Those sending units are the sensors and they do go bad quite often. Also the other problem is that the wire clips are sometimes loose on them and can come unplugged with natural ease. Of course your problem sounds to be a possible bad sending unit.

First I would start the car and let it idle until its to operating temperature and check the gauge. If your oil pressure is lower than it should be at that time then pull the oil fill cap and see if its slinging enough oil up around on the cams and such. If it has plenty of oil slinging around in there and the gauge reads that its too low then that tells us the sending unit is in fact going bad. If there is not enough oil being slung around then that means there is a larger possible problem. (oil pump going bad, oil filter clogged, oil pickup clogged, etc.)