Fluctuating Oil Pressure/Noisy Lifter

[FooBag]

My dad's 2001 Buick LeSabre has an odd intermittent oil pressure issue going on that I am at a loss to explain. Some days, when the car is driven, the engine is silent and the oil pressure gauge reports 50-60 PSI of pressure. Other days, the lifters will be making tons of noise, and the car will only maintain oil pressure in the low 30's. The problem seems to be worse after the car is heat soaked, for example, after a highway road trip.

Does anyone have any ideas what might be the issue on this? The car is not burning or losing oil. I was thinking of dropping the oil pan to make sure there was not something in it partially clogging the pickup tube. I really doubt the oil pump has failed, given how rare that situation is.

[Bio248]

i would also point towards a clog if i had to guess.

[blueguy]

Right...since it is a crank driven pump. Things I would check...since I've had a few oil pressure issues...you might try seeing if the accumulator is sticking in the oil filter housing...its a PITA to take off and you have to drain the oil out...but you'll also be able to see if there is build up in the oil filter housing itself perhaps causing it. You can buy a '04+ Grand Prix Supercharged (L32 engine code) Accumulator/Spring Kit for like $5 or so...and it is actually a big stronger of a spring so it bumps oil pressure by about 5-10psi. If that is the issue it could cure it right there...just food for thought. Next thing I'd check is the pan...sucks...but there might be something in the pickup tube...who knows. Do you have a mechanical gauge on it to test the pressure? I'm guessing so from your readings you were giving us. How many miles are on the car? Driving conditions? Has it ever sat for a long time? Maybe something is gunked up? Could be lots of things LOL

[VinnieGTP]

First things first I would just go to a thicker viscosity oil and see if the problem persists.

[FooBag]

Thanks for the suggestions, guys. No mechanical gauge for testing the pressure, bu this LeSabre has a pressure readout on information center. I'd say it's semi accurate, as when the pressure reads high, there is no noise and when low, the lifters are noisy. I have one of the 04+ accumulators in my pile of parts in the garage, so I can definitely try that option. Dropping the pan won't be too bad as it's not completely trapped in place like on the W-body.

The car has between 80-100K and gets driven regularly. It hasn't sat for any extended length of time. My parent's are int he 60's so there's no wild driving going on with...

I was also considering running some Seafoam through the oil in the hopes it might take care of whatever might be in there.