Well, for my first car my dad bought me an Olds ''95 Cutlass Supreme SL 3.1L for my birthday. It is in beautiful condition considering its age, and we got a pretty nice deal on it. It has 130,000 miles, but it was babied all the way through and never abused. We know the guy who we bought it from, and he treats everything he has meticulously.

Now, the biggest apparent problem with this car is that there is a loud knocking noise when shes idleing. It becomes much less aparent when in the car, and when you increase the revs past idle, you can''t hear it at all. Now, after the car has been running for a while, the noise isn''t noticable, even when outside the car at idle. A quick diagnosis by a local repair guy brought us to think that piston slap was a posibility, but he said it was really impossible to tell. What do you guys think? Its really a distinctive and loud noise, and its quite embarassing. Also, if you happen to have an idea what it is, is there anything I can do to fix it? I should also mention that the intake and filter are both clean and all fluid levels are good. We know it will probably one day come down to an engine swap, but we want to do everything we can do to fix it because its a beautiful car.

Thanks in advance for any help.

 

i am 99% sure i know the problem.


My oldest brother had a 95 monte carlo with a 3.4 liter


his had a loud constent nocking at idle but went away after a higher motor RPM. He took it to a dealer and said it was a piston nock but the only problem with it is its a "lifter problem". When the car is idling the lifter doesnt load with enough oil to keep lubricated and makes a nock, but after a higher RPM the pump pumps enough oil into the lifter to keep lubricated, thus making the noise go away. I would strongly suggest maybe not replacing the motor if you dont need to, it just might need new lifters or a new or higher velocity oil pump.

 

Sounds exactly like my problem. It does go away at higher RPM, and it seems to become less prominent after warm-up, which makes since because the oil won''t be as viscous so more is moving. That makes sense. Now I just have so see if I want to replace the lifters or the oil pump, or just run it until it dies.

 

yeah it might only be a bad lifter if the lifters and cam never got replaced but im sure they did after 130,000 miles, so most likely just the lifters but if the cam hasnt been replaced i would suggest that too because you can make that car last a looong time if you take care of it.

 

Or just keep it at high rpm... Only kidding
Be well!
Travis

 

Neither has been replaced, ever.

Maybe I should look into that then?

 

i would look into it if it sounds like its a problem


but if you do replace them, replace the cam and the lifters at the same time, because it would cause unormal wear on the lifters if you just replace those, and something else might go wrong.