Non confirmed missifire at idle

[Escott1622]

2001 986 2.7 80k miles. Randomly starting this morning when I started the car I got a slight rough idle with no CEL. Car revs up and even drives and feels like it has most of it power but once you are at idle it sounds exactly like the car has an aggressive cam. I did replace the AOS 10-20k miles ago and only get white smoke maybe once every few weeks when the car sits for awhile. Is there any like big things that normally cause this I should check? I’m used to engine codes. I do have a smoke machine I can use but can’t get to the car till next week. My lift is occupied so I figured I’d use the next week to see what you guys think, will probably replace AOS while I’m in there because of the white smoke. New spark plugs and several coils in the past 10k miles. I’ve normally always had check engine lights to diagnose so this is a first for me with this car not getting one

[Escott1622]

Air filter also replaced recently. Has secondary cat bypass pipes and from what I think it has original o2 sensors. Only use 93 octane

[Escott1622]

One of the things I plan on looking at is cleaning the MAF sensor maybe it’s dirty or because of AOS it has oil or something on it

[JayG]

Could also be a coil pack

[JayG]

***** duplicate post ******

[Escott1622]

Used the smoke machine, the rubber hose that’s on the bottom of the AOS had a massive hole in it. Replaced and ran fine

[Josdek]

I'm dealing with a similar issue, may I ask where you injected the smoke? Thanks.

[Escott1622]

Smaller hose that goes into intake tube. I’d know if I saw it