Its the drains. use compressed air and blow out the tubes. I used an E string for a bass Guitar but its too tensile. My '95 525iT leaked like **** in random places until I blew out the drains now a major Southern rain doesn't touch the interior.

Great forum, I called Bruno the week that I got the car 10/2003 and have been lurking ever since. Luckily. Now I have misfiring problems....