I have a 2003 530I, After heavy rains here in the Northeast, my driver's side rear floor mat and the floor itself was soaking wet. any clues as to where I should start looking for leak
My neighbor had exactly the same problem in her 2002 530i. It caused the whole electrical system and computer to fail and now she has major damage. I had a similar problem in my 2002 525 sport wagon and it turned out to be the door liners. After about 5 years the glue fails and the sheet of plastic just falls to the bottom of the door. Once we got it fixed the water never came back. BMW is very aware of it, however it's not cheap to fix as the part is nothing but there is a fair amount of labor as they have to take the door apart. I hear it was a design flaw.
I had it even worse, My front door seems to be taking in water and wet my LKM. But i had FIRE Dealer claimed it was my sunroof seal leaking but after the second LKM getting wet i took apart everything myself and found a collapsed pass door seal. And i paid over $1200 for the fire damage and another 300 bux for the dealer to find the WRONG LEAK. http://bmwcca.org/forum/showthread.php?t=6880
Do you think BMW should pay for this as it appears it was something they knew about and should have let owners know?