I recently purchased a 2016 M235i xDrive and a few days later (after it got really cold out here in Michigan) I noticed a very annoying “whistling” wind sound coming from my driver side window. I took it to the dealership I purchased it from only for them to tell me they “didn’t hear anything” (typical dealership BS) so I started looking for a DIY solution.
My first thought was to replace the weather seal or readjust my window alignment but both were time consuming/expensive (especially since it seems to only happen in really cold weather)
Ultimately I ended up finding this
solid core foam/rubber tubing that fit PERFECTLY into the existing weather strip gap. Problem completely solved, no more wind noise at all, and looks pretty sharp IMO!