Hey, I drive a 2014 Mercedes E-Class diesel and had similar symptoms to yours a few months ago. For me it was actually a cable/plug fault. The check engine light and strange engine noises were really annoying. I also noticed this jerking when accelerating. My mechanic was able to find the fault after a bit of troubleshooting. A broken plug was then replaced and a damaged cable repaired. It wasn't a trivial fault, but my mechanic said it was necessary to repair it to prevent anything worse. My car has been running great again since the repair and I haven't noticed any more of these symptoms. So it's quite possible that your X-Class has something similar. Hope this helps you.

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Hey, thanks for your quick response. I'm a little reassured to hear that it wasn't a major fault in your case and could simply be fixed with a cable/plug fault. Do you happen to remember how much the repair cost you and whether any other problems have arisen since then? It would be helpful to know what costs I should be prepared for. Thank you very much!

(Translated from German)

Hey, sure, no problem. The repair cost me around €95 to fix the faulty cable/connector. I was really relieved, I have to tell you. And as far as the knock sensor is concerned, everything has been running smoothly again since my visit to the workshop - it was actually malfunctioning. But since then there have been no further problems and my car is running like clockwork again. So don't worry, hopefully it's the same with your sled. All the best!

(Translated from German)

Hey, that's a real relief to hear! 95 really sounds like a reasonable investment considering how much a new car would cost. And good to hear that no further problems have occurred since. You've really given me hope that my X Class might be similar. Thank you so much for your help and words of encouragement. Well, I'm going to head to the garage and hope it's just a minor problem. Wish me luck! Thanks again!

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