Hey, I had similar problems with my 2018 Mercedes A-Class. I also had the check engine light on, black smoke coming out of the exhaust and the engine running rough. It turned out that the engine control unit was faulty. Similar symptoms such as loss of power and vibrating at idle were confirmed in my case. The repair in the workshop was quite extensive. The engine control unit had to be completely replaced and reprogrammed. After that, the engine ran smoothly again and all the problems were solved. This is definitely a serious matter that should not be ignored. I would recommend that you go to the garage as soon as possible and have it checked. It's better to act early before anything else breaks. Good luck!

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Hey, thanks for your reply! That sounds pretty similar to my problems. Can you tell me how much you paid for the repair? And has anything else come up since then? Greetings!

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Hey, no problem, you're welcome! In my case, the repair cost €1000 because the engine control unit was completely blown and had to be replaced. But since then everything has been running perfectly again and no new problems have arisen. The problem you suspected with the ignition coil or misfiring was also resolved as soon as the control unit was replaced. So it was really worth it, even if it did hurt your wallet a bit. Hopefully everything will be fine for you too! Keep your fingers crossed. Greetings!

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Hey, thanks for the info! 1000€ is of course quite a lot, but as long as it's quiet afterwards, it's probably worth it. I won't waste any time then and will go to the garage as soon as possible. Hopefully it's not quite as bad for me and can be fixed more easily. Thanks again for your help and tips! Greetings!

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