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SariVog

Mercedes CLA power loss, engine jerks and the check engine light is on

Car won't start

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Check engine light on

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Jerking on acceleration

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Loss of engine power

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Poor fuel economy

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Black smoke from exhaust on acceleration

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Stalling while idling

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Unsteady engine

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Shaking while idling

Hey everyone, my 2015 Mercedes CLA (gasoline, 219876 km) is currently having problems. Symptoms are: black smoke from the exhaust when accelerating, check engine light on, loss of power, rough engine running, jerking when accelerating, won't start, high fuel consumption, stalling at idle, and vibrating at idle. I suspect a defective ignition coil or misfiring. Has anyone had similar experiences? How was your visit to the mechanic? I would appreciate your tips and experiences! Thanks a lot!

(Translated from German)

4 comment(s)


LionBraun

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!

(Translated from German)

SariVog (Author)

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!

(Translated from German)

LionBraun

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!

(Translated from German)

SariVog (Author)

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!

(Translated from German)

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