Lately with all this talk regarding the X3's exhaust I too am curious about the golf tee mod. I found a video showing the simplest method for doing this mod and all it requries is for you to unplug a cord in the trunk versus plugging a valve with a golf tee. I have located the cord in our X3 and have included a photo but would like to see if anyone else has done this mod and by which method you used, thanks in advance.