Hello, I am the third owner of the 2003 540i 6 speed (it has an M package). The car is never been in an accident as far as I know. But, when I take the car through the local power car wash, the back door seals fail and I get water on the rear floor boards. (I had a 1998 540i 6 speed with no such problems.) The seals look fine. The doors and body line up. but ... there's a leak on BOTH sides???? The water comes in with a hard rain and when it goes through the car wash. Help me. Peter
I can't remember off the top of my head if the e39 rear doors had a double seal system. Meaning one seal around the door and one around the body. But if both those are not torn or damaged, I would remove your rear door panels and inspect your weather insulation to see if its damaged this can also cause a leak on the floor of these vehicles. Good luck
The prior owner may have had to remove the interior rear door panels for some reason, maybe to replace window regulators. If that happened, the interior moisture barrier may have been torn or may not have been properly resealed after the repair. Suggest that you remove one (find how-to videos on YouTube) and see if the barrier is broken or not sealed. If yes, likely the same problem on the other side. Good luck!
thanks for the input ... I have taken my water hose and forced water along the top of the back doors. It seems that the water only comes in when the water is forced at the point of the side window (stationary window) of the back doors (both sides). So I thought it would be an exterior seal problem where the door slopes downward towards the rear of the car. Each door has 2 seals and I can't imagine that all 4 seals are failing (on the 2 rear doors) all at once. Does this still sound like a weather moisture barrier problem??? I have (once) felt under the door (where the door panel fits on the door) for moisture coming from the interior of the door ... nothing. I'll try this again today as I take it through the wash. I also have some special tape that leaves no marks (clear film) that I will mask off the top of the doors to see if the water is coming from the top of the door. I can do the same tomorrow and mask off the actual rear window (all four sides) and see if the windows on each door leak to the interior. VERY frustrating. thanks, Peter
This is a known problem with the E39; I had the same problem with my 525. After a hard rainstorm or a car wash, my rear floor mats would be soaked. But it wouldn't happen all the time, which was maddening. It probably had to be a monsoon, or a situation like a car wash where the water was shot at the car forcibly. There's info all over this site and others about what to do, and as pointed out by eblue540 above, there's YouTube how-to videos. Good luck finding and fixing this issue...
