Ok, This problem started about three weeks ago and I haven't driven the car but a few times trying to determine the problem. At startup, oil pressure is 80-90 psi when cold. Then when it warms up, has around 15-20 at idle - normal (always been this way). The engine is fresh, maybe 2000 miles on rebuild. If I rev the engine in neutral, the guage jumps to 50-60 psi. But as soon as any load is on the engine, the pressure will not rise and even starts to drop. I changed oil and tried a different filter. Was using a Wix so I tried an AC Delco PF52, same thing happened. The engine makes no noise what so ever, very quiet other than the normal lifter noise. Now, the lifters rattle EVERY time I start it from cold, but they quit after 1-2 seconds - normal. However, the lifter noise at startup seems to be getting worse, but always quiets after 1-2 seconds as I stated before. I've read every oil pressure post on here I could find. Problems from heat sensitive sending units, to colapsed pickup screens to bearing failure. I may be wrong, but logically it doesn't seem possible to have a considerable drop in oil pressure (if bearing related) and not have some rattle or knock of some kind. Tonight I drove the car a few miles to warm up the oil, pulled back in the garage and popped the hood to listen around. The bottom end is quiet as can be. I revved it up to 2500-3000 rpm for a few seconds trying to hear some bearing rattle, but it's just not there. I guess my questions are: 1) can a colapsed lifter or worn lobe cause this problem? 2) Could the sending unit be heat sensitive?-except under load is the only time this occurs-load equals heat and the sending unit is very close to header and radiator hose. 3) Is this bearing related? 4) Can the oil pickup tube cause this?-load wouldn't seem to be relavent here. 5) Could this be cam bearing related?
I know it's innevitable that I'm gonna have to tear into this thing, but I want to get as much info to begin with before I start. The only thing recently that I've changed on the engine is a steel braided oil feed line to the turbo. I can easily swap this back, but couldn't see how this could possibly have any bearing on the situation at all - no pun intended!! Any thoughts?
I know it's innevitable that I'm gonna have to tear into this thing, but I want to get as much info to begin with before I start. The only thing recently that I've changed on the engine is a steel braided oil feed line to the turbo. I can easily swap this back, but couldn't see how this could possibly have any bearing on the situation at all - no pun intended!! Any thoughts?
