lq4 low oil pressure
 

A little background I installed a cam, springs and rods. Drove great for 4000 miles. I changed the oil with 5w30 mobile 1 and noticed what sounded like lifter noise. 2 days after that it sounded like something was in my engine with a wrench beating it up. Tore into it sure enough bad lifter. Pulled the lifter and the bearings fell in the oil pan. The cam had no damage, so put the top end back together. Took the oil pan off and the crank sheild got all the metal out inspected crank everything looked fine. Put it all back together started on the second crank ran great but had 5psi pressure. When I give it gas it goes up to 40. Let off goes back down. Haven't put a gauge on it to see if it's a bad gauge. About to pull the oil pan and check the o ring on the pick up tube. Any ideas??? Thanks in advance.


Brendan

How many miles on the engine?

About 140k

Try a manual gauge and a new oring. Be your easeist trouble shooting.

That's what I thought just wanted to get some opinions. I have had some buddies tell me different things from it could be the o ring, the valley cover or the pump. I wasn't sure if the pump failed that the pressure would go up if I gave it some gas.

If it's bad you will hear the lifter noise. When mine went out, I actually heard it before I looked down and noticed the gauge lighting up. The relief valve was stuck open. I went with an LS6 pump. Yes a stuck open valve would show pressure if you raise the RPMs but don't chance it. Probably not the Oring if you didn't mess with it recently.

Probably a dicked up lifter bore...

I should have read the whole story... Yeah if you pulled the pickup tube to look at the crank and didn't replace the O ring, that's probably the problem. Make sure you get the correct one for your year of engine. Some have a recessed area on the pickup tube and some don't.

I hope that's it. I've been out of town haven't had time to mess with. Hope it's not the lifter bore but don't think it is. It looked ok and the lifter was still together until I pulled it out. The new lifter felt like the other lifters in the block. I plan on doing the o ring and inspect the pump soon. I'll let y'all know what I figure it out.

finally had time to work on it sure enough it was the o ring for the pump. Popped right in like an injecter. I don't want to start another post so I have a question. I took the front drive shaft diff and cv axales off thinking I would have a rear wheel drive beast instead of all wheel drive. Diddnt move. Wtf??? It's fwd or what?