PontiacBonnevilleClub.com

My 96 Bonneville SE has had some issues with the oil gauge. The gauge itself will stay in place for a good majority of my 55 mile commute. After a certain amount of miles, usually when I'm about 3/4's of the way through my trip, my car will start riding very rough. When I say rough, I mean that I can feel vibrations/rumbling in the steering wheel, brake pedal, and gas pedal. After that point, the oil gauge needle will start to flicker back and forth from the third notch to the second notch (the one marked with 40) and when I take my foot off the gas or brake, it will go down to the red area and start ding-ing. When I go back to accelerating, the needle will go back up and everything will be fine. I recently had electrical work done on one of the grounds in the front. I know my oil is not low, as I recently got an oil change.

How many miles are on the car? It could very possibly be a faulty oil pump getting ready to fail.

While it's not unheard of, a failing oil pump is pretty rare in the 3800. Which oil filter was used when the oil was changed? Does the engine make more noise (knocks, tapping) when the pressure drops? Have the intake gaskets been replaced? Are you losing any coolant?

I'm with Archon. The one oil pump failure I've seen was when the pump broke into 3 pieces.

Maybe a bad sensor? My 92 SE oil gauge flickered until I replaced the sensor and it fixed the problem

I know mine on the 2000 SSEI when the oil sending unit went bad it just pegged out my gauge to max with no warning lights or no running issues. When I replaced it my gauge went back to normal pressure.

I only stated a possible bad oil pump because I have sold many believe it or not since working for AAP. Most of the people who buy them had complained with the same exact problem that the original poster has stated. It is probably unlikely his is bad, however, the possibility is still there. Maybe with cheap oil filters it has allowed the oil pickup screen to get partially clogged. I hope for the posters sake it is a simple repair such as the oil sending unit, please repost back on here with a little more information such as mileage, oil filter and oil used, and if problem started before or after oil change.

Check the oil pressure sensor prior to droppping the pan you may get lucky and not have the pump go.

Just so you know, the oil pump on these is a gerotor, and located in the front cover. To get at it, you have to remove the balancer, waterpump, etc. There is very little to wear/fail. I'd be looking closely at the pickup and the oil pressure sender.