This is a messed up problem, I hope you guys can help. I have a 92 Z28 W/Rebuilt 350TPI.
the oil pressure will drop almost to the redline when there is a load on the engine, but if I'm cruising on the highway it's fine. Also, after I chagne the oil I don't have this problem at all, it's only when I get about 1800-2000 miles on it It's really pissing me off! Can you guys help me out here???

 

change your oil every 1500 miles

 

Thanks Smart ***! Butthat doesn't really help me much

 

If the oil level ok, i'd check out the integrity of the gauge. The gauge could be bad.

 

The guage? How would the guage only react to higher mileage oil? You should check the sender. Make sure the connections are good. Makesure its clean - any crud or buildup could cause a false signal.

 

he's right,check the sender .I had a similar problem,changed the sending unit ,and the problem went away.if I remember right it was under 15.00

Hope this helps

 

Thanks for all the info guys, I'll check on that sender this weekend!!

-Marc-