Oil pressure guage acting up

It just started yesterday.I noticed that my guage was pegged way past 80.Then when I started it back it was fine.Then when i restarted it was pegged again Ect.Is this an electrical problem or is it like the old kind that has a plastic tube that has the oil in it.How do it fix this?

Yours being an 82, would have an electric oil pressure gauge. 

Does this mean I need to replace the guage or a sencer?I guess I can check my shop manual or my assembly manual.Thanks,at least I know what type of guage I have.

I'd start with the sensor, it's the cheapest, easiest way out and most often the problem.

It is most likely going to be an electrical problem. The gauge "peggin out" means the sensor wire is shorted somewhere(maybe around the exhaust), or the gauge itself may be losing its ground. Check the sensor area first, and see if the wire to the sensor is touching the exhaust, or has a worn spot in it somewhere that is allowing it to short. If you disconnect the wire at the sensor, the gauge should show "0". If it doesn't, then you have a short in the sensor wire, somewhere, or a bad groung to the gauge.