Maybe you can replace the pulleys with the Weistec ones. AMG tech I know has a 09 C63 and 11 ML63 and he put catch can and those pulleys in both because he said our stock pulleys arent the best.

 

PLOT TWIST

This morning I went to my mechanic and we pulled off the belt and ran the car to see if it still produced the sound. It still did! After poking around with the stethoscope we discovered the source of my issues... Exhaust manifold gasket has a leak!! It starts to hiss around 3,500 rpm due to the increase in exhaust gas pressure. As the revs increase from there it continues to leak more and more air, creating a louder sound and decreasing the amount of gas reaching the 02 sensors downrange, resulting in less fuel for that bank of the engine, which is causing the misfires and lean code after pushing the motor. Got the parts ordered! Say a prayer to the AMG gods for me fellas, I'm hoping this solves it.

 

So? Did it fix your problem? Or was it the maid with the candlestick?

 

I continued this issue here. Quite the turn of events from such simple initial symptoms. https://mbworld.org/forums/c63-amg-w...not-quite.html

 

Misfire cyl 1 and 3
Hi guys I have a problem with my 2009 c180 k few days ago I pulled away from a red light and the engine light came on and the car was very sluggish and shaking I pulled over and turned the ignition off and back on again to no avail I've changed the plugs and attempted to check the coils and it still has the same shaking I plugged in the code reader and got the following P0303 P0301 P0300 can anyone please help I'm out of warranty and I've run out of ideas

 

Don't thread-jack.

Post your issue in the appropriate section (here).

 

Best of luck mang, hope that solves it!