Oil pickup o-ring issue
 

I have searched but couldn't find much. Does anyone have a video or a sound clip of the issue with the cut/crushed o-ring in the oil pickup tube? What I thought to be a lifter tick for awhile now has me wondering if it's this issue with the oil pickup tube because of where the sound is originating from. I doubt this is my problem but it is a possibility. I heard a video of an ls1 car that had a crack in the weld on the headers and it sounded identical to my noise but I really do not think my sound is coming from the headers. If anyone has a video of the o-ring tick please share. Thanks

How's your oil pressure? If your o-ring is pinched or cracked, your oil pressure will suffer.

It has been acting up. One minute it's normal then it will drop down to around 10-15 then to 0 the back up to 40... here is a quick video of when it first started. Pretty much everytime I drive the car it does this now. I was thinking it is thhe sending unit on its way out but now I'm not sure

Usually when the sensor goes, it just pegs at the max. What's happening might be a crushed/cracked o-ring. It's a lot easier to replace the sensor than the o-ring, I'd try changing the sensor first to see if that has any impact, then go after the o-ring.

Was any work done to the car involving the oil pump? (cam, timing set, oil pump replacement, etc)? Does your ticking get better/worse with changes in oil pressure as indicated by the gauge (lower, louder ticking, higher less ticking)?

I am replacing the sensor this friday so I will go from there. I don't believe there is any change in the ticking as the pressure fluctuates. I haven't really been outside of the car when this is happening so it's hard to say but I do not believe there is any change. The oil pump and everything in the motor is stock.

I'd get a real mechanical gauge on there ASAP to verify real pressure.

How's your oil level? I had a scare once where oil pressure was very low, freaked out thinking it was a mechanical problem (pump, etc)

It turns out I was just a couple quarts low on oil

Outstanding point. Something seems fishy if the car is 100% stock.

Oil level is perfect. I am taking it to a shop friday so I will have them check it out. This whole time I have just been thinking the sending unit is bad but now Im wondering if I have a bigger issue. While driving it goes back and forth from normal pressure to very low pressure. It will show normal for a few mins then bottom out then back to normal.

I would also pull the lower half of the oil pan (if you have the 2 piece pan) and check the screen for any debris. That's easy enough to do.

I just recently changed my oil, wish I would have done this :banghead:

If the oil pressure dropped to zero like shown in the video, you would have heard a lot of noise from the lifters. I suspect the sending unit or possibly another electrical issue.

Does the digital oil pressure show similar variation?

I haven't actually watched the digital pressure when it's happpening. I do actually have pretty loud lifter noise but it's the same when the pressure is at 40-50psi as when it's showing 0. Also it does not run any different when showing low either. I have an appointment friday at a shop that is an hour away to have the sensor swapped and also doing the rocker trunnion upgrade but now I'm questioning whether or not I should drive it that far with it showing such low pressure.

So just an update, got my ops changed and oil pressure is normal now. I assume the oil pump is fine and I do not have a cut o-ring because I have not had any pressure issues since the sensor was changed. Had my mechanic take a close listen to the engine tick I've had going on for awhile now and he feels certain that it's down in the motor. He removed the belts and the sound did not change. I was crossing my fingers that I would get lucky and it be an exhaust leak but its looking like new lifters are in my future.

Since this is a C5 and between 15 and 21 years old, IMO o ring should be replaced unless you know it was changed in the last 2 years. Why wait?

What all is involved with changing it, just dropping the oil pan and unbolting the pickup tube?

Pretty much. The seal gets hard and can crack allowing air to get sucked in oil pump.

The O Ring that can be "pinched" is at the oil pump.. It's where the pick up tube fits
into the oil pump itself
The only way to check it is to pull apart balancer, timing cover, water pump, etc
It's quite a bit of work

That's what I thought... if it were pinched or cut there would be oil pressure issues though, right?

Yes.. Some came from the factory screwed up.. Usually run fine and act fine..
Just less oil pressure all the time.. Lose about 5-10 psi..
They ARE hard to assembly, so I can see how the factory pinched a few..