BMW: 2002 540i water problems/second part, vapor barriers, body man

Question
hi.  i forgot to mention that recently someone hit my driver's side door in a parking lot.  the door shell had to be replaced and some other door work was done.

i've also had to have the thermostat replaced recently.  can any of these things cause water to collect behind the front seats on the rear mats and on the rear carpet, but not in the middle or trunk.  someone mentioned that it could be the rear footwell vents

is this a common problem with the E39's?

thanks for your help.

Answer
Sorry to hear about the wreck, I hope everyone was okay. Logic would tell me that if this water problem has occured since the body work then the body work caused it. If the shell was damaged enough to warrant replacement there is a chance the a or b-pillars could be tweaked as well. We are only talking about .5mm clearance between leak and no leak. Also if the door was replaced I can almost promise you Billy Bob at the body shop doesn't know the importance of the vapor barrier in a BMW. It has to be 100% intact. If it was a reputable body shop thy will stand behind their work. Bottom line is get it fixed, there are modules, harnesses, and fuses under the carpet you are damaging. If you have water in the carpet then there is 3 inches of water under it. I am sticking with my guess on the vapor barriers, like I said-about 90% of the time a body man or random tech replacing a window lift has caused that problem. Please let me know.