So the car developed some rough idling a couple weeks ago, does not appear to have an issue when driving (power is good). Only when stopped or in park. Decided to do a plug change as it had been a while. Also cleaned MAF's and new airfilters - well misfires still happening. CEL starting blinking, ran Vag Com and came back that all cylinders have random misfires. No other codes. Gregg (fellow RS6 owner) came over a we looked at some measuring blocks and initially saw cylinder 4 having a higher count of misfires, but then another also showed a higher count than the others. Car also smells to be running rich (car always had a somewhat "rich" smell even before this, but now much stronger as it is obviously misfiring). So one question, would 1 bad coil pack cause a cascading effect to influence all others to act up? It seems unlikely that all 8 packs have or are failing at the same time. Also if a coil pack is bad, shouldn't the misfiring occur under load? Another comment was maybe bad gas - (always gas up at the same place), I could add a bottle of de-moisture treatment and see if that helps ??? Just a bit puzzled.

TIA - Scott