Mercedes M Klasse Diesel Performance Problems Solved

I had similar performance issues with my M Klasse diesel a while back such as rough idling and sluggish acceleration. Have you checked the injection valves for dirt or debris? Clogging in the injection system can definitely lead to those symptoms. Has the vehicle had any recent fuel system maintenance?

The prospect of clogging seems plausible. When you experienced similar difficulties, did a diagnostic scan confirm the injection nozzle issue? Were any specific error codes generated that might aid in my assessment?

The diagnostic scan did point towards the injectors. I don't recall the specific error codes, but the mechanic confirmed that the injectors were not spraying fuel correctly. Given the symptoms you described and the mileage on your vehicle, it's probably best to have a workshop examine the injectors directly.

Following your advice, I entrusted the vehicle to a qualified mechanic who confirmed a defective injection nozzle. The repair cost 515€, and involved replacing the faulty nozzle and cleaning the remaining components. The vehicle now operates flawlessly, exhibiting a return to its original performance levels. Thank you again for your time and expertise.