I have 1990 coupe and experimenting a weird problem lately: On WOT, the oil pressure drops suddenly to the red and goes back up if i let the gas pedal go. Does that in all the gears at all speed...
Aftermarket or stock gauge? The stock oil pressure sending unit dies often, so it might be as simple as replacing that if you're using the stock gauge.
is it possible that you are actually pumping all the oil out of your pan and actually loosing oil pressure? do you have a high flow oil pump and a regular pan?
The pcv is 7 bucks mine as well replace it if its never been done anyway. By the way stock gauges suck especially electric sending unit oil pressure gauges. To really tell oil pressure you need to tap into the oil gally plugs on the block with a meachnical gauge.
