Audi Q5 Hybrid Power Loss and Engine Knock Alert

I had very similar issues with my 2013 Audi Q7 Hybrid, and as someone with some basic car maintenance experience, those symptoms instantly reminded me of my situation. The engine knock and power loss turned out to be caused by carbon deposits in the combustion chamber. The knock sensor was actually working correctly by detecting the irregular combustion patterns. The workshop confirmed this after running diagnostics. The fix involved: Complete combustion chamber cleaning, Replacement of fouled spark plugs, Fuel system cleaning, Reprogramming the knock sensor parameters Total repair cost was 425 Euro and resolved all symptoms: No more engine knock, Power restored, Smoke eliminated, Warning light cleared Going forward, I now use higher fuel octane and do more frequent maintenance to prevent deposit buildup. To provide more specific advice for your case, could you share: Current mileage, Fuel type typically used, When symptoms first appeared, Whether piston slap noise is more noticeable when cold This would help determine if your issue matches what I experienced or might be something different.

After completing my latest service at 167426 KM, I discovered the problem was indeed related to poor engine tuning and incorrect fuel octane. My mechanic confirmed severe pre-ignition issues in multiple cylinders, which explains the power loss and engine knock symptoms. The knock sensor was triggering correctly, detecting abnormal combustion chamber patterns. After running comprehensive tests, they found the engine management system needed recalibration and the fuel mixture was running too lean. Fixed by: Engine control unit recalibration, Cleaning injection system, New spark plugs, Higher grade fuel Total cost: 380 Euro All symptoms cleared after these repairs. Running much smoother now with proper combustion and no warning lights.

Thanks for the detailed update on your Q5 repair outcome. Interesting how your fix was similar but not identical to what I dealt with on my Q7. In my case, the carbon deposits were the primary culprit causing detonation, while yours stemmed more from engine tuning and fuel management issues. Both scenarios triggered the knock sensor, but the root causes differed slightly. The repair cost difference of 45 Euro makes sense given your fix focused more on calibration rather than the extensive combustion chamber cleaning I needed. Pre-ignition issues can often be resolved through proper engine tuning and fuel management, which aligns with your successful repair approach. Something to consider, since both our Audi hybrids seem sensitive to these issues, using fuel additives designed to prevent carbon buildup might help avoid future problems. After my repair, this preventive step has kept detonation issues at bay. Have you noticed any change in fuel consumption since the fix? My Q7 showed noticeable improvement once proper combustion was restored.

Following up on my Q5s repair, yes, fuel consumption has improved significantly! Getting about 15% better mileage now that the ignition timing and fuel mixture are properly calibrated. The engine tuning changes made a real difference in how the car performs. The detonation issues are completely resolved, no more knock sensor warnings or power loss during acceleration. I appreciate the suggestion about fuel additives. Started using them alongside higher octane fuel and the engine runs noticeably smoother, especially during cold starts. One interesting thing my mechanic mentioned was that these hybrid models can be particularly sensitive to ignition timing issues. The interplay between the electric and combustion systems requires precise engine tuning to prevent pre-ignition problems. The investment in fixing the engine knock problems was definitely worth it. Not only is the car performing better, but preventing potential long-term damage from continued detonation makes the 380 Euro repair cost seem reasonable. Just glad to have it sorted before any serious engine damage occurred. The proper diagnosis focusing on engine tuning rather than just replacing parts saved both time and money.