XC40 Knocking Combustion Issue

My 2016 Volvo XC40 with a gasoline engine is showing signs of knocking combustion at 214908 km. I've noticed reduced power, jerking when accelerating, and smoke. Also, there's an error stored in the memory. Could it be combustion chamber deposits?

4 comment(s)

That sounds rough. I had similar issues before. Have you tried a fuel system cleaner? Also, when did you last check your knock sensor? A faulty one could be feeding bad info to the ECU.

I haven't tried a fuel system cleaner yet. How can I effectively test the knock sensor to see if it needs replacing?

Testing knock sensors can be tricky without the right tools. Based on the symptoms, especially the smoke, and the error codes, it's probably more than just a sensor. Deposits in the combustion chamber seem likely. I'd advise a workshop visit for a proper diagnosis to prevent further damage.

I consulted a mechanic, and the diagnosis confirmed excessive deposits in the combustion chamber, causing the knocking. The repair, including a thorough cleaning, cost 425€. Thanks for pointing me towards a professional assessment.

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