I did two runs, this log is the second, but both times the fault code was a misfire in cylinder 1. A while back I had a very fouled plug in cyl 1 but was also having PCV system issues at the time and thought it was related to that. I replaced the plugs and I have noticed that it's fouling again, also the ceramic in cylinder 1 was chacked around the electrode on the old plug and the new plug has also started to crack. Also the old front turbo was very black in side when we replaced it yesterday, where as the rear turbo was "normal". Could this in conjunction with the differences in STFT between bank 1 and 2 could indicate an injector issue in bank 1, potentially cylinder 1?