Hi,
My recently acquired Century is in great shape and I’ve been catching it up on all maintenance.
Spark plugs, transmission fluid and filter, even cleaned and silicone sprayed seat belt webbings(what a difference it made).
But I still notice that at idle I hear a rattling sound.
With my head in the engine compartment, it seems to be coming from the drivers side, the transmission.
Any easy fix for this!?

It’* not the typical piston slap, because I can slightly hear that from under the car.

ThankX

Maybe record it for us.

Moved from Pontiac Bonneville section to Buick forum.

Yeah, record it.

Any chance the noise is coming from the catalytic converter?

Thanks for moving, I couldn’t find the Buick 3.1 Forum section!

You know, now I haven’t been able to hear it.
i hear the piston slap a bit down below but not the strange rattling from the transmission bell housing area.
I even have a cheap automotive stethoscope with a long rod that works well. But All I hear is the seems normal mechanical and bearing sounds.
Ive tried to repeat the short drive and then parking with the idle when I did hear it.
Well I’ll repost here if I catch it again, I’ll record it.

Sorry, thank you for the input..!

Fixed is fixed, but yeah it would be better if we found the problem.