I have a 2004 X3 with 70k miles on it (although this fix will work on any leaking sunroof). I purchased this vehicle new (it was a program car). My X3 never lived outside (it had always been garaged) until I started spending extended periods of time with my fiancé two years ago (my work requires only an internet connection and an airport).
Once it lived outside, the car started leaking after every heavy rain (and when I say leaking, I mean all I needed was the koi to have a once worth $50k now worthless piece of…German engineering become an upscale pond using the floor of my vehicle). It has been in the shop numerous times since. Over the last two years, I’ve spent hundreds in having BMW blow out the panoramic sunroof drains (they eventually showed me how to do it) and hundreds more in replacing the driver’s door vapor seal. Nothing has resolved the leaking. So, I put on my closet engineer hat and came up with the following workaround. My fiance is an engineer and was impressed by the effectiveness of this workaround. (Not meaning to pat myself on the back, but desperate times leads to desperate measures.)
First, let me say that this workaround is 100% effective. It is also very inexpensive ($150.00), but it may not be All That for everyone.
What I did was find a location that installs 3M Paint Protector film, also known as the Invisible Bra. I've used the Invisible Bra product on all of my BMW’s so I had a company called Tint King install a sheet of the 3M Paint Protector film across the top of my car.
(Actually, they installed two sheets with about a 1/4” overlap at the sunroof seam due to the size of the panoramic sunroof - as well as about 4" around the edge of the sunroof, totally sealing it from the elements. See pictures below.)
The film is completely see through (you would never know it was there) so you can open the shade and get full sun. You can also see out the sunroof as if you were looking through glass alone. You cannot, however, open the sunroof, which is why this workaround may not be for everyone. But, for me, that is more than acceptable.
I was lucky enough (or unlucky enough) to have tornadoes rip through the area - along with another round of torrential rains the tornadoes brought with them - the day after my install which allowed me to test my workaround. The car interior was completely dry.
I used Tint King (in London, Ontario – I am an American who spends much time in Canada, as my finace is Canadian. Tint King did a GREAT job and the car has not leaked during any of the subsequent rains, including the one that brought the tornadoes. There are Tint King locations throughout the US and Canada (I used Google). You seriously cannot tell the film is on the top of the car. It is crystal clear. (The film is also 100% removable should you desire to remove it at a future date.)
Sorry for the reflection of the car's interior. I snapped these with my cell phone right after installation and there's not much to see other than gray and blue sky.
Note that the remaining water from the installation has completely dissipated and the film is flat and perfectly installed. They couldn't initially squeegee out that bit of water due to the lip around the sunroof.
An Unconcerned BMW of North America:
When I called BMW of North America to ask them to help me out with drying the underside of the mats (IOW pay the labor to pull up the mats and dry the vehicle once and for all), they told me tough luck. I need to eat my German engineered crap sandwich and enjoy it. The cost for BMW to dry out the flooring under the mats is more than $600 which is all labor.
I was told that BMW is completely unaware of any leakage problem in their vehicles and it was my responsibility alone if I wanted to dry out the cabin floor. I tried to get some pages of a manual to show how to pull up the carpets so I could do it myself and was told to check YouTube (I couldn’t find one that applied…if anyone has some help/instructions for pulling up the front cabin carpeting it would be greatly appreciated - email welcome.) I was told that there were no design problems causing leakage and too bad for me.
I told her I was a three time BMW owner (new 2001 X5, new 2004 X3, used 1999 318ti) and was looking to get a new car in the upcoming months and that I had a hard time justifying buying another BMW when I didn’t feel that they were standing behind their product in what is obviously, reading all the BMW boards, a design flaw. Enjoy my turd sandwich was the only response.
A couple of other things; the installed carpets show no sign of mold (something I won’t know fully until I can lift those carpets up). The BMW floor mats molded badly. Once I removed them, the smell immediately went away. I will not be replacing the BMW mats. I am going to solely replace my ancient WeatherTech rubber mats.
As an added bonus, the cabin is much quieter now that the 3M Paint Protector film is across the top of my car. It used to have more wind noise than I would like with the shade fully open. No more.
Lastly, my vehicle is older (though I am the only owner) so I probably have little leg to stand on in a class lawsuit, but I think that owner’s experiencing this disaster with their once worth tens of thousands of dollars but now worthless pieces of…German engineering should band together to get some kind of compensation. Seriously, who is going to purchase my or your leaking BMW disaster? In my eyes, this is unacceptable for a premium brand.
Now that I no longer have the leaks, I will keep this guy until it’s time for me to get a new car and then I will probably give it away to one of my friend’s kids or donate it to a good cause.
Sorry for the length of this post.