Fahrer

The only other thing I can think of is;

1. Possibly aged coil packs. The housings can deteriorate and moisture can get in resulting in misfires?
2. Dirty mass air flow sensor ( MAF) ?
3. Dirty oxygen sensor?

OLI77

Nop, no lights or signs on the dash. No codes.

OLI77

I will look into cleaning my MAF this weekend since that is an easy thing. Good idea.
Is that guy near the air filter box? Can someone point me to it?
Could be the coil packs. Changing the plugs did nothing.
Thanks

Fahrer

The MAF sensor is between the airbox and the intake manifold. Generally, there are flexible connections with hose clamps that can be removed. The electrical connector needs to be unplugged as well. Be very careful handling the MAF sensor ( do not touch any of the internals). MAF cleaner can be purchased at any auto parts store. Please note that my information is generic and I have not opened the MAF sensor on an Audi. You can do a search on these forums or look to YouTube to get a video.

Regarding the coil packs, I would simply inspect them for cracks.

OLI77

Thanks Farher, I found it, took it out (from the filter box) and cleaned with MAF cleaner. Letting it dry now before I start it up....
I had taken the coil packs out when I changed the plugs and had not noticed anything weird other than old baked dielectric grease around the outside.

Will report back soon if MAF cleaning took care of things on a cold start.

OLI77

Well I'll be!

I noticed a much smoother engine on the first cold start after cleaning the MAF! It was not perfect, but that seems to have improved the smoothness (less sudden/ acute engine vibrations) quite a bit.

Will see if it stays this way...

OLI77

It only stayed clean like that for about 2 weeks. The mild perturbation is back. I have learned to live with it. All good.