Misfire and code issues

[Austin.colson1]

I previously posted with an issue about misfire codes.
I have a 2011 335i coupe. First my car stopped running completely, I had power but my engine would not turn over. I replaced the starter, battery, and the fuel sensor. It started running but was misfiring so I replaced the the spark plugs and coil packs. Now cylinder 6 is misfiring so I replaced the fuel injector on cylinder 6 and still getting a code for misfire on cylinder 6. Any ideas what else I can try?? I've had this car for a month and I am regretting buying it even though I love the car. I also had exhaust work done (muffler delete) professionally. I had the exhaust shop check it again and it is not due to that work. It only seems to have problems when i give it gas. Now I had a buddy run his OBD2 and got a list of additional codes. His OBD2 did not show a misfire on cylinder 6 bur instead on cylinder 4. Maybe because my OBD2 was a cheaper $70 pepboys code reader. Any ideas? Below are a list of the codes from my buddy.

E597- ECU Center control module (in drivers footwell) (FRM)
E59A- ECU Central module (in drivers footwell) (FRM)
E594- ECU Central module (in drivers footwell) (FRM)
E59C- ECU Central module (in drivers footwell) (FRM)
E9C6C- Climate/heater/air conditioning
29D0- Engine control unit
29D0- Engine control unit #1