Originally Posted by AWD Addict
Been working on it with my independent mechanic now that I'm out of warranty. THe answer is no. I can tell you it's a miniature misfire though, as it's worse when my plugs are bad.
I'm inclined to believe its just something that's a part of the car at this point, coincident with the other finicky elements like injectors, coil packs and plugs. I think this car is just a very fine tuned vehicle with very little margin for error given the amount of technology used for its operation.
I think we should all be changing plugs every 20k miles (minimum, if you're tuned, less). I'm at almost 20k since mine were done, and I've noticed my mileage is down too. I'm about to get them swapped. I'll record a couple tanks and report back if that's in fact related.
I'll venture to say that finicky in the N54 engine you speak of comes predominantly from the carbon build up on the intake valves. I finally got around to walnut blasting mine out last night and believe this picture speaks perfectly to the majority of direct injection turbo engines that run rough or misfire.
48k miles, all 6 cylinders were complete shit, pic is at the start and then during the blasting process of one of the cylinders, not the finished outcome but eye-opening to say the least.