hi, I have a 92 APV when in gear it idles rough when i put it in neutral or park it idles smoother not as well as it used to but better.
Any thoughts?

im assuming this is the lumina APV?

Older vehicles generally have a mechanical adjustment for idle for both neutral and while in gear.

Yes it's a Lumina APV.
3.1 shifts great and smooth but rumbles while in drive while stopped.

Sounds to be a vacum leak.Spray some WD40 around hoses if RPM changes you found the leak

Most vehicles "bog down" a bit when shifting into gear....................not a lot, but they do

Sounds to be a vacum leak.Spray some WD40 around hoses if RPM changes you found the leak

I'd recommend a carb cleaner more than WD40. It works, but carb cleaners will burn better and not leave any residue behind.

could also be some carbon build up in the egr valve.............