OK if i'm in neutral the oil pressure is at about 25psi, then I can rev it to redline and it will go to about 50psi like normal. But if i'm getting on it the oil pressure will be at like 50psi and then when I step on it the oil pressure will start to go the opposite direction This isn't using the stock guage, this is with my autometer electric oil pressure guage that has been working fine for the longest time so I know it's NOT the guage.

Does this mean that my pickup fell off? Any Ideas?

 

The next time you drain the oil, tap on the bottom of the oil pan with a plastic hammer or one those compothane Snap-on deals and see if you hear the pick up moving around in the pan.

You could also use a wire in the drain hole or if your Howard Hughes, you could look in there with a bore scope. Seriously, a lot of shops have a bore scope and would be glad to look in there for you. For a fee I'm sure.

If the pick up is on, the alternative isn't good.

 

What year is your car? If you look in advanced tech they determined that 93-95 cars will do this b/c the oil stays at the top of the engine. The fix is a new, larger pan with a different oil baffle. Supposedely GM sent out a statement saying early LT1's will do this, and that they are not going to experience more problem b/c of that (something like 25psi at 6500 will make bearings hot enough to spin). I dont know how accurate their info was but my has done this for quite a while. I just got used to it. You will find it will only do it past about 4k in first (in my 2.73 auto anyways)

 

No, it never used to do this before so this isn't something that is normal.

 

The 355 in my old 77 Z28 used to do that. The high pressure/volume pump would suck the pan dry. After seeing that twice, I switched to a 7 qt pan and the problem was gone. Since you say your car hasn't done this before, it would be worth it to have the scope put into the oil pan and have em check it out.

 

The same thing happend/happens to me. It was pretty freqeunt right after I changed my oil, but it hasn't done so in the past 300 miles. I would get it at WOT after I stopped accelerating in 2nd gear. I usually shifted at 5300 in 1st and popped it into nuetral to slow down (I usually did this on 45 mph roads) at 4000-5000 rpm. Right after I stopped accelerating, my check gauges light would turn on and the oil pressure level would drop to the red. I waited about 3-5 seconds and it always went away. It may just be me, but if my foot was on the clutch, the pressure would come up quicker.

I didn't do anything to fix it, it just seemed to go away.

Todd

 

chickenscreamer is 100% correct on this subject

 

could be clogged filter, oil cooler or low oil as well.

 

No he's not, didn't you read? The guy said that his car never used to do this before

 

Most interesting, and a question I posted a year or so ago.

My motor is a stock rebuild, with the exception of SRP higher compression pistons. Under WOT the oil pressure dips to 15 - 25 PSI or so, but WILL NOT stay there. It just looks like the gauge looses power for a second or two. At redline, the oil pressure is up there for sure. It just appears that the initial acceleration is what does it.

I've tried 5w50 Castrol, 5w30 and 10w30 Mobil 1 (which I currently run), and twice 20w40 and the SAME thing.

Can somebody direct me to this post in Advanced?

(I have a 94)

 

Same problem here, at 5000rpm steady its 70psi with MV55 pump, but under acceleration it drops off above 4k until I shift, mine happens in 1,2,3 gears, I have a blower which also might contribute to the problem. I also think my MV55 pump has the pickup welded on. Are the oil return holes too small, what are some fixes besides a bigger pan?