Hi, I had similar symptoms with my 2016 Skoda Octavia diesel. Black smoke, Check Engine Light, and loss of power often indicate a problem with one of the lambda sensors. At my garage, they had to replace one of the lambda sensors. The sensor was defective and was sending incorrect values to the control unit, which was causing all the problems. After replacing the sensor and resetting the control unit, the engine ran smoothly again and the problems were solved. It was not an insignificant repair, but nothing unsolvable either. Just go to a competent mechanic and it should be done quickly. Good luck!

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Hey, thanks for your reply! Do you remember roughly how much the repair cost? And has anything else come up since then? LG

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Hey, yes, of course, the repair for my Octavia cost a total of €375. This was due to the replacement of the defective lambda sensor. Since I've been to the garage, the exhaust aftertreatment malfunction has actually been rectified and nothing has come up again. Runs perfectly again! 😊 LG

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Hey, thanks a lot for the information! That really helps me. Now I'm at least a little more reassured. I'll make an appointment with my garage as soon as possible and hope that it won't be too expensive for me either. I'll report back here when everything is running again. Thanks again and best regards!

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