My 2002 E320 4matic Wagon has been fairly reliable. For two years, I have been hearing this nagging intermittent rattle that seems like it is coming from front passenger side dash/windshield area behind glove box. It almost sounds like hood is rattling. My mechanic has triple checked all suspension and even taken off front right wheel well to check for loose parts, brackets etc. We even had the sunroof checked and installed extra insulation. It is driving me nuts and no one can seem to locate it. Of course it never makes the noise when you need it to. It is the original windshield. Also had heat shield adjusted. HELP!!!!!