Most likely it's not your cam shaft but the cam shaft adjuster. You must have a fault for engine timing, possibly something like camshaft is advanced or retarded, during diagnosis they can test you engine timing and see if it Passed/failed these tests. The cam shaft adjuster uses oil pressure to adjust the cam timing during normal engine use. Something could fail in this component requiring replacement.
Replacement of a 2008 Chvy Camshaft Sensor
The cast of Frau Mercedes - 2008 includes: Sylvia Leiser as Frau Mercedes
It's in the center of the inside of the engine.
The 2008 Mercedes-Benz G-Class has 24 valves.
The 2008 Mercedes-Benz GL-Class has 24 valves.
The 2008 Mercedes-Benz SLK-Class has a V6 engine.
The 2008 Mercedes-Benz SL-Class has a V8 engine.
The 2008 Mercedes-Benz E-Class has 24 valves.
The 2008 Mercedes-Benz CL-Class has a V8 engine.
The 2008 Mercedes-Benz M-Class has a V6 engine.
The 2008 Mercedes-Benz S-Class has a V8 engine.
The 2008 Mercedes-Benz E-Class has a V6 engine.