I had this problem, I just changed the leads and the problem was gone.

 

I just received this problem myself with my 2003 C230 Kompressor Sedan Sport. I pull off for school and im listening to my music loudly ( i have subs and all ) and i come to a stop light and i feel my car shaking and i think to myself my subs are shaking then i second think and say wtf. i turn the music down and it is still shaking as if big foot is aside my car shaking it back in forth. i also notice that my engine sounds like it is tyring to rev up by itself. example: (vroom vrooom vrooom). with 50,000 miles i hope it is nothing too major.. when i get home from school i turn on my car put it in drive with my friend having the foot on the break and i pop the hood and i see my engine basically moving from side to side making me think that the reason the car is shaking is because the engine is shaking back and forth...ive been reading on forums and i think it may be engine mounts??? i have no knowledge of cars so thats why i am here seeking help before i go to the dealer and they charge me for a whole mess of stuff i really dont need. help needed extremely! thanks!

 

Paypapboi, did you ever find the problem? I'm having the problem now on my 2005 C240 Wagon with 53k miles.