Mercedes B Klasse Hybrid Engine Knock Issue

I also drive a Mercedes B Klasse, though it's a little older. I had similar symptoms once, including the error code. I'm not certain about the knock sensor specifically, but could it be cylinder heads or potentially needing some engine tuning? Have you checked for error codes? Is the smoke black or blue?

Thanks for the input! The error code points towards knocking combustion, making me think about the combustion chamber. The smoke is black. If it was cylinder heads I imagine the smoke would be blue. What was the eventual fix in your case?

Black smoke probably rules out cylinder heads then, though I'm no expert. My issue also turned out to be combustion-related. Carbon deposits were the culprit. I'd suggest getting it checked at a workshop, since cleaning the combustion chamber can be tricky. They'll probably check the knock sensor too while they're at it.

Appreciate the confirmation and advice. Booked an appointment at the shop, and they confirmed the deposits in the combustion chamber. Cleaning it cost 425€. Runs smoothly now!