When I bought my M3W I had the timing pulley upgrade fitted before collecting it. I then had similar problems with starting, sometimes first crank but mostly not at all, the latter particularly when warm. I did however notice that the RH exhaust popped more than the left. The garage collected the car, checked it over and said that it was down to a poorly fitted woodruff key! Sorry I can’t be more specific but I’d only had the car one day when it happened and so I didn’t do my own investigation. At the time it seemed to me that starting depended on which cylinder was on first compression?
