well, earlier this year before i got my series 2 in the harmonic balancer got chewed to bits and had a massive delay and a terrible knock. guess what, 3 months later and i think its happened to the series 2 motor. i had a massive delay and backfiring only in 3rd 4th and 5th and i was wondering if this could be the harmonic balancer? it also has a massive delay and rough running in neutral, almost like its out of time. how can i check its the balancer and not something internal? thanks guys.