Hello, I have rain coming in my rear doors - 2003 5 series with M sport package. Only when heavy downpour and then it collects inside in the rear passenger foot well (both sides). I can't localize it but it seems to be coming from the seals (all look good to me), not from the ceiling or from undercarriage. Any help is apprecitaed on solving. Thanks, Peter
Ever had your window regulators replaced on either rear door? Maybe a prrior owner? If so, good chance that the moisture barrier liner was not properly resealed when they put the door back together. Test this way: sit inside the car. Have a helper run a hose one the window of a rear door, full gushing flow of the hose. In a few minutes, look for a trickle coming in from the bottom o the door into the interior of the car. Pretty easy DIY fix if this is it. Let us know.
It's most likely the moisture barrier inside the rear doors. I've had a few E39's and all of them have suffered from this problem. I agree it's a DIY repair, there are videos on YouTube that show the process well. Otherwise I suggest finding an independent BMW tech and they can do it in about an hour per door.
