VW Amarok Engine Knocking After Recent Timing Adjustment

Had similar symptoms on my 2013 VW Passat 2.0 TSI. The detonation issues were caused by carbon deposits in the combustion chamber after a poor engine tune. Pre-ignition and knocking occurred because of incorrect ignition timing combined with low fuel octane. Key findings from my repair: Carbon buildup on intake valves and cylinder heads required chemical cleaning, Timing had to be reset to factory specs, Spark plugs showed signs of pre-ignition damage, ECU needed recalibration to factory settings The mechanics found serious carbon deposits affecting the combustion chamber efficiency. They performed a complete top-end cleaning, replaced the spark plugs, and properly reset the timing. This resolved the power loss, smoke, and knocking issues. Recommend having them: 1. Check fuel octane rating 2. Inspect cylinder heads for carbon buildup 3. Verify ignition timing settings 4. Test fuel injector spray patterns 5. Run complete diagnostics for stored codes This was a significant repair requiring specialized knowledge. Best to address it quickly before potential engine damage occurs.

Thanks for sharing your experience with the Passat. Those symptoms do sound exactly like what I am dealing with. The carbon buildup explanation makes a lot of sense given my car behavior. Do you remember roughly how much the complete repair cost in the end? Also wondering if you had any other issues pop up since they fixed it? My main concern is getting this sorted properly on the first try this time.

The complete repair came to 425€ for cleaning the combustion chamber deposits and resetting everything properly. Since getting it fixed, the engine has been running perfectly with no knocking or detonation issues. The proper engine tuning made a huge difference. The mechanics found that incorrect fuel octane combined with poor ignition timing had caused significant carbon buildup. Getting this resolved with a thorough cleaning and proper adjustment prevented any lasting engine damage. Make sure they do a complete diagnostic check and valve cleaning, its worth paying for a proper fix rather than partial solutions. The key is addressing both the timing and carbon deposit issues together, not just one or the other. Its been about 8 months since my repair with no problems returning. Just using the recommended fuel grade and keeping up with regular maintenance has kept the engine running smoothly. You should see similar results once they properly clean the combustion chamber and reset everything.

Thanks everyone for the detailed advice. Just got back from the mechanic and wanted to share how it went. The repair cost came to 390€ which included cleaning out all the carbon deposits and properly resetting the ignition timing. They found the knock sensor was actually damaged during the previous service which explained the detonation issues I was experiencing. They did a thorough cleaning of the cylinder heads and intake valves, plus replaced the faulty knock sensor. The piston slap noise I was hearing is completely gone now. The engine feels much smoother under acceleration with no more pre-ignition or power loss. Really glad I brought this up here first, helped me know exactly what to ask them to check. Been driving it for a few days now and its running perfectly. Going to stick with high octane fuel and regular maintenance from now on to prevent this happening again. Feel much better having it properly sorted by a shop that knew what they were doing this time around. Thanks again for pointing me in the right direction with the carbon buildup issue.