So recently in my 2007 335i, the mosfet driver system went bad in the MSD80 DME, so obviously we switched to a MSD81 and sent it off with the CAS and injector codes in order for the proper coding of it. We put it in and found that we had some bad coils, so we replaced every coil and that should have been the end of the problems, but alas, more codes have surfaced. I am getting misfires in cylinders 1, 3, and 4 (although 4 is very occasional). The only codes that appear are the misfire codes and nothing else, so we checked the coils and spark plugs, switched them between non-misifiring cylinders but to no avail, the codes remained in the same cylinders. I plan on going over the injector coding to see if that is the fault, but any other ideas in case that isnt the answer?