So it looks like my oil pressure issue due to the sludge has caused some additional problems, most likely with the turbo. The car is noticably down on power now so at present am assuming that the turbo bearings have been damaged due to lack of oil for the short time the oil pressure was down. I'm a bit pee'd off tbh. Car going back to my local indy next week to try and find out exactly what the problem is and how much £££'s it's going to cost. Does anybody know anywhere to get K03s turbos from?