I chip tuned my N54 with the JB4 and did intake, downpipes. Had 204k miles on it when I sold it and got my M4. Only ever had one major issue when the water pump died. Sometimes I would get a few misfires and that would be my cue to change the spark plugs, which would fix the issue immediately.
I chip tuned my N54 with the JB4 and did intake, downpipes. Had 204k miles on it when I sold it and got my M4. Only ever had one major issue when the water pump died. Sometimes I would get a few misfires and that would be my cue to change the spark plugs, which would fix the issue immediately.