[E93Dude]

I don't know enough about the different symptoms of a MOSFET failure to give you much more insight into whether or not it is truly responsible for the issues that you are having. Others on e90post know about this than I do.

But what I can tell you, is that given that you have swapped the coils and injectors, your problem may be with the ignition system (the ECU and maybe MOSFET). Have you checked your car's OBDII port for fault codes? You don't have to have a "check engine" light for there to be fault codes stored in the ECU. If you don't have bluetooth OBDII reader, and app for your phone - GET ONE. They are cheap and excellent diagnostic tools.