Better check your oil pressure with a mechanical gauge. Same problem here and I'm redoing the bottom end right now, rod bearing knock!

Most of the time its a bad sensor so I wouldn't panic just yet. You HAVE to confirm it with a mechanical gauge first. My car does the same exact thing and it hasn't gone south on me in the 2 years I had it and the 15k I put in it. It could be a weak pressure relief valve, dirty or corroded sensor contacts, or simply that your sender unit is crap.

Unless you've been leaking coolant into the crankcase (already ruled that out) or anything else that would damage the bearings I highly doubt that at that mileage your L67 would be going south, it would only be plausible with an L36 due to the infamous "torching" around the stovepipe.

Yep this sounds like what happened to my car oil pressure would go down to almost nothing sometimes at idle but then when you give it some gas the oil pressure would shoot right back up Before it was known that the main berring was on the way out my car would sometimes just kill no power at all and then would have to just drift over to the side of the road but then after waiting o a few minutes it would fire right back and id be right back on my way mine was still driveable but eventually I got a horrible knocking and after bringing it to the mechanic and putting some new parts on I found out that the engine was shot anyways

Good Luck with that and if your berrings are shot I hope you stay with this car and fix it or get a new engine

I'm planning on hooking up a mechanical gauge sometime this week. well i had the oil changed and added lucas treatment, and put 500 miles on this weekend. The oil pressure is higher then it has ever been since i purchased the car. cold start up i get 60psi, warm under power, it sits around 55psi and at warm idle it sits at minimum 38psi. there were no metal flakes or shaving in the oil at all, and i have never seen any since i bought the car at 91k. I will probably replace the pcv valve when i hook the mechanical gauge up. if the sender unit is good, and i was getting that low of oil pressure, i am probably going to sell the car, before it gets worse. I love my bonneville, but it isn't worth putting a new engine in, and i still owe $4200 on my loan. What kind of cost is there in rebuilding the bottom end of the engine? Are there any kits available?

thnx

This may or may not have been caused by a bad batch of oil, and by coincidence it happened as the temps got warmer outside, i don't know. We'll see what kind of things i find out this week.

My daughter has a 94 Bonneville she loves...150K on it. 3800 engine, runs great but oil pressure drops when warmed up. If it is the main bearings..(I hope to get the pressure checked soon with mechanical gauge) how much does it cost to replace the bottom end? Is it worth it?

I had low oil pressure for a while, and nobody could tell me what they thought was wrong. I almost went out and bought a high-pressure oil pump, but then when I took my car to get inspected, just this week [at the same garage that I took it to RIGHT before the oil pressure started dropping- same day, actually] it seems to have been fixed, but I don't have a recipt or anything to show it.

Now, it still dings around corners, but that'* just because the oil'* low, it leaks out so I have to put a quart or so in every so often. But the pressure isn't nearly as low as it used to be. Not sure if it was right, but the gague used to show somewhere around 5-10 PSI when the engine got hot.

And, dunno if yours makes the noise, but the constant ding of the Check Gages light was what drove me crazy.

should hear the lifters tapping. Most of the time it'* a bad oil pressure sensor. I have a test for that some place. I'll try to post that asap.

Low oil pressure started happening to me all of the sudden about 2 weeks ago. The oil pressure is fine when the car first starts up, like around 50psi, then after about 15-20 minutes of driving (when the engine temp is at or above 200F), whenever I come to a complete stop the oil pressure dramatically drops to 2 or 3psi and the check gauges sound goes off. Scared of seizing the engine, I put the car in neutral and rev to slightly above 1000rpms which makes the pressure gauge rise again to about 40 psi. Then when driving normally, the pressure always reads slightly less than 40psi.

I just recently (about a month ago) got the LIM replaced at a shop where in order to do the job, they had to change the oil and filter, so both those are very fresh. I figured out on the summary sheet for the repair that they put in 5w-30 instead of 10w-30 like it says on the oil cap. I then looked at the dipstick and it reads 1/2 inch over the full mark. I did some research and found out that overfilling the oil can cause aeration, and thus low pressure, could this be what I'm experiencing?

So far I've found out that low oil pressure can be caused by: overfilling the oil, worn out rod/main bearings, clogged/worn out pump or filter, or a bad pressure sensor. Based on what I've said, is anything here more likely than the other. It'* hard for me to hear ticking valves because my coupler is rattling. Trying to troubleshoot, please help. (I'm buying a mechanical oil pressure sensor soon)