[Formulajones]

Originally Posted by gto4evr

Hello again....this car's starting to bug me now. got the starting issue sorted out on that other thread (thank you again!) and the other issue I thought was just a bad gauge apparently isn't.

background again:
69 GTO

400 4spd, basically stock rebuild in 2007

This year when I pulled the car out of storage, I noticed my oil pressure is very high out of no where. I've got an aftermarket oil pressure gauge on the car since I didn't trust idiot lights to the fresh build and ended up just leaving it under the dash. From the beginning of the motor build in 2007 up til last year, I'd get 40 psi at a cold start idle, once the car was all warmed up, it floated around 20 psi at idle and 60 under a load.

this year when I pulled it out of storage, other that the starting issue (now solved) it ran great, but would hit 60 psi cold start up, 80 under a load, then after completely warmed up it doesn't drop below 40 psi. I figured the aftermarket gauge was just dying so I just replaced it with a new one, and.....same results.

cold start just now, sitting at 60psi idle and hits 80 when revved up.

after fully warming the engine up it idles at 40 and revs at 60. engine temps are always fine at a consistent 195 just like it's been for the past 14 years. changed oil and bled the line to the gauge, no difference.

So any ideas on the sudden change to idle pressure? I searched the forum but couldn't find any similar threads.

It could simply be that the 1st gauge was inaccurate, maybe corrected itself during a long hibernation????, and the new gauge you're now using is okay as well.

I wouldn't worry about it. 40 at idle and 60 at higher rpm when warm is pretty common and probably closer to what is really going on. I have a few engines here just like that and they've been happy for years and thousands of miles, Pontiacs and Chevrolets.