SQ8 Misfiring

[Raven6Actual]

I picked up a sweet 2020 SQ8 a couple of months back and all has been well. Two things happened around the same time, I took it in for a 30k service and I put in a BMC oiled air filter (a terrible idea in retrospect).

There’s no Audi dealer within three hours so I called the local VW shop. They said they could handle the oil change and spark plugs for a reasonable price. It took them much longer than they expected since they initially had the quote from a V6, but they got it done.

I picked it up and drove it home with no issues. The next morning, I noticed the CEL and took it back in. I was worried they did something wrong and so were they. They reported misfiring in cylinder #2 and suspected a bad plug. They ordered a new batch to be sure, but replacement did nothing. They then noticed some red oil residue on the #2 cylinder coil and suspected the BMC. They ordered another coil and replaced, but the misfires continued and even moved around, all on the same bank of cylinders 1-4, mostly on 1 and 2.

They removed everything and cleaned out more residue claiming there was a soda can full. I’m sure that was an exaggeration, but still some was removed. They then thought it was a “sensor” fouled with oil. I asked about a MAF, but they said it does not have one. I’m unsure if they were talking about the O2 sensors on the cats. Regardless, they swapped them from left to right thinking the misfire would move to the other bank, but it didn’t.

They removed the oiled filter and out in a OEM one. They have been running the car at idle for a couple days hoping to burn off excess oil, but claim the misfire is actually worse. It’s mostly cylinder 1 now. They have no more ideas and admitted the engine and problem is beyond their knowledge, they have had the car for two weeks now. They have called Audi looking for any known issues that might cause this, but think it may need to be towed three hours away for “expert” eyes.

My question is could excess filter oil cause this and why? I know they can clog an MAF, but apparently there isn’t one. It’s oil, so if it gets anywhere else shouldn’t it just burn off eventually? Could it have fouled the O2 and they need cleaned or replaced? I didn’t get a straight answer if they cleaned those sensors before the swap. If not the oil, what else could be the root cause?

Any thoughts or ideas would be appreciated.