VW Arteon Performance Drop with Smoke and Jerking

I experienced similar symptoms with my 2017 VW Passat GT. The symptoms pointed to carbon deposits in the combustion chamber, which was causing pre-ignition and detonation issues. The knock sensor was repeatedly detecting these problems, leading to the ECU adjusting timing to protect the engine. The fix required: Combustion chamber cleaning service, New spark plugs, Fuel system cleaning, Knock sensor testing and calibration The root cause was using lower fuel octane than recommended. After switching to higher-grade fuel and completing the repairs, the engine performance returned to normal. The jerking and smoke issues completely resolved. This was a serious problem that needed immediate attention, as continuous detonation can damage engine components. The symptoms you describe strongly suggest similar issues, particularly the combination of power loss and knock sensor involvement. Recommendations: Get a diagnostic scan focusing on knock sensor data, Check fuel octane rating youre currently using, Have the combustion chambers inspected for carbon buildup, Consider a full fuel system cleaning These symptoms should not be ignored as they typically worsen over time and can lead to more extensive engine damage.

Thanks for sharing your experience. That sounds very similar to what I dealt with, especially the detonation issues and piston slap symptoms. My Arteon had the exact same jerking sensation during acceleration. Just wondering, how much did the full repair cost in your case? And have you noticed any recurrent issues since the fix? My main concern is making sure the problem gets solved permanently rather than just masking the symptoms with temporary fixes.

Just wanted to update on the repair costs since you asked. After visiting my mechanic last month, the total came to 425€ for fixing the carbon deposits in the combustion chamber and related work. The detonation issues and engine knock completely disappeared after the service. The fix has been permanent with no recurring problems. The engine runs smooth now, especially during acceleration. No more piston slap sounds or power loss issues. The key was addressing the root cause through proper engine tuning and thorough combustion chamber cleaning rather than just treating symptoms. Make sure your mechanic does a complete fuel system cleaning along with the chamber service. Using the recommended fuel grade since the repair has helped maintain the engine performance. Zero complaints after putting about 5000km on the clock post-repair.

Thanks for the helpful advice. I finally took my Arteon to a different mechanic yesterday who diagnosed the exact issues mentioned here. The knock sensor readings confirmed the pre-ignition problems and carbon buildup. The total repair bill came to 480€ which included: Complete combustion chamber cleaning, New spark plugs, Fuel system service, Engine tuning adjustment The difference in performance is remarkable. No more jerking or smoke during acceleration, and the engine power is back to normal. The proper ignition timing has made a huge difference. Already put 200km on it since the repair and everything runs perfectly. Lesson learned about using the correct fuel grade and not delaying these kinds of repairs. Really glad I switched mechanics too, the new shop did thorough diagnostic work instead of just guessing at the problem.