Chuffing noise, diesel smell in cabin, black crusty residue around injectors. What the manual dictates: You cannot just pull the injector. The manual specifies using a dedicated puller (e.g., HAZET 2780-4) and a carbon reamer to clean the bore perfectly. It also lists the exact tightening torque for the injector clamp bolts (typically 7 Nm + 90-120°). Failure to follow this leads to repeat failures or cracked cylinder heads.
If you skip step 4 or 5, the bolt will fail, the pulley will wobble, and the timing chain will jump—destroying the engine. Mercedes Workshop Manual Om646 Engine
The is a 2.1-liter (2,148 cc) inline-four cylinder diesel engine manufactured by Mercedes-Benz between 2002 and 2010. It is a highly robust "long-life" engine noted for its usage of a cast-iron crankcase, common rail diesel technology, and widespread implementation in E-Class (W211) and Sprinter vans. Designation: Sold primarily as 200 CDI and 220 CDI. Chuffing noise, diesel smell in cabin, black crusty