Any info on this yet?
Holding wood with my stage 2 S6 (used to have issue, power hesitations on semi boost low buildup, but was able to sort it out with OEM plugs and exhaust modification -> X pipe instead of H on the milltek).
What i do noticed is and experienced a few times of the 3-4 years i have my car...the car doesn't like low fuel! Each time it is very low and i fill her up, the next day she tends to idle roughly and misfire.
Each case is differently offcourse (but especially if the car isn't throwing codes)....but just sharing

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Hope it isn't a turbo failure (please do 5k oil intervals as the oil screen is a know cause to starve the turbos....see Paulm

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Plugs every 30.000km even if audi says 60.000km

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Don't push her untill she is warm enough and give her time to cool down

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