What do you mean when you say erratic. This brings back memories that I JUST fixed. To me it means when I picked up my car and the oil press needle was all over the place...about 40, 120, 80, 40, 120. worse than a fish floppin around outta water.
The only true way to find out if you have crazy oil pressure is to pull out the sending unit (near oil filter on my 95) and test with a mechanical gauge. I bought the sending unit figuring it was the sender. Never took it out of the package after reading up in techinfo about gauge problems with these clusters. Do any of your other gauges near the oil pressure gauge seem to be off as well?
If yes you probably have a bad cluster. If only the three gauges water temp, oil press and alt/boost are acting weird you can follow techinfo article to remove and clean/reseat the circuit boards. Or change the one amsll circuit board (confirmed this last night) that plugs directly onto the gauge posts for those three gauges. Or you could change the entire cluster.
If your other gauges are reading properly I would check the sending unit first. It'* pretty cheap and easy to replace. The chance your pressure is just really high due to a clog is not common, but don't rule anything out.
00 Regal GS: All kinds of cool stuff.