Ok, I dunno whats going on, but when I start my car, the oil pressure is off the scale at 420 kPa or w/e. As it warms up it drops down. When fully warmed up, the car will have say 100 - 150 kPa while driving but when I stop at a light or something, it drops right down into the red and basically is touching 0. the car runs fine, ive actually been running it like this for awhile, i know im dumb yadda yadda yadda, but could it be a problem with my PCM or the oil pressure sender itself maybe?

 

if all else is well it sounds like just the press. sensor . its the thing sticking out above the oil filter . be careful with the plastic plug going to the sensor . the plastic gets brittle with age . good luck .

 

How 'tired' is your engine? Also, has this happened slowly over time or all of the sudden?

I have seen different brands of oil (same viscosity) run at different pressures in the same engine. You could go for the next higher viscosity if you have a high milage or high wear engine on the next oil change.

 

is it smoking? less power?

if not, probably just the sending unit or gauge.

 

I have a quick question about psi also. My stock 91 L03 with 10-30 conventional and a hot day idles at the line before 30...but scales with RPM. is this normal? I wasnt sure so i threw 20-50 in it to see if it helped and it really jacked up the PSI. People told me it was too thick for my mileage so i took it out and puttin 10-30 synthetic mix in it. (btw would about 2k miles with that thick oil kill my motor?)

**sorry for the hijack**

 

get a good mechanical hand held oil pressure gauge and it will tell you if it's the sensor or the bearing clearances are beyond help.

 

I just rebuilt the engine, the crank was turned down like, .017 or .018. So, I had to put .010 over bearings in it, ..010 + .005 for oil clearance right? If i had put .020's in it wouldn't have worked period. The oil pressure was way up at 420 kPa ALL the time before the rebuild, so I am thinking it's just the sending unit... I wasn't sure if there was a way to test the unit other than using an oil pressure gauge, since I don't have one :P By the way I broke it in with thick oil then changed it back to 5w30, not much of a difference in readings between the change.