I took out my door panel for a window regulator problem. When I was driving without the door panel. It made a much different sound than with it. I would suggest what the previous post suggests and also making sure that the panel is set right. Also, in Japan the cars have no safety reinforcements or safety beam in door. It is not mandatory. If your car was hit. I would assume the safety beam in the door would be damaged if, it was not exchanged out for another door. The reason why I am saying this is, b/c my friend in Japan opened and close the door of my former 300ZX TT in the US. He drove one in Japan and said there was a huge difference in weight and sound of the door vs. the Japanese versiou due, to the safety beam or reinforcement in the door. You can see the safety beam in the door if, you take off the panel I assume but, don't know if the tar-like material is hindering this view. On my 560, you can see it and touch it after, removing the panel. Hope it helps but, I honestly don't know the specifics of your model. It is just a guess.