Well thats a tough one, try searching the forums for Sunroof problems and see what comes up, also try searching for sunroof adjustment, and other terms related to it. you should find a ton of useful information regarding the sunroof operation and fixes people have done.
In my case, a little grease was needed as the track was bone dry and the roof would skip a bit or slow down to a crawl. now its smooth and moves at a constant speed until it closes. When I would pitch the roof the left side would stay down, so I greased the pivots and that cleared that up too.
People have removed their motors and all, so Search for sunroof in the forums and you should find some helpful information.
Metallic Black (Blue Flaked) on Parchment
Black Grille Insert
17" AMG Monoblocks or EVO II's
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