Hey guys, got myself an 05 fpv BA F6 MkII, and just recently I've noticed that it is surging around 4000-5000rpm. As long as its under boost it gets there then the rpm will stay at that level for a second or two then keep going up, or it will even drop down a few hundred rpm then go up again. Anyone having the same problem or had it previously and know how to fix it??? Im thinking spark plugs or clutch slipping, but dont want to replace the clutch due to the price of a f6 clutch :/ spark plugs easy enough but didnt want to waste money on them if its not needed. Any help would be greatly appreciated, cheers!