Alright so I have a 2002 E53 3.0i which occasionally won't start. The issue seems to stem from the positive battery cable as usually after a jiggle it some I can get it started. I really don't mind this however it is a slight pain because I have a subwoofer installed in the back along with an amp. Now before anyone blames the subwoofer I had it professionally installed and I've checked the fuse and all connections in the rear and they seem to be completely fine. If anyone else has had this same issue and found a fix, I'd love to know. Thank you