Audi A8 Engine Misfire Points to Faulty Moisture Sensor

I had a very similar issue with my 2015 Audi A6 last summer. Having some experience with basic car maintenance, I first tried checking the moisture sensor connections myself, but quickly realized this needed professional attention when the malfunction indicator kept returning. The car sensor problem turned out to be exactly what you described, rough running during acceleration and persistent check engine warnings. After taking it to a workshop, they performed detailed sensor testing and discovered that water had gotten into one of the main connector plugs, causing intermittent connection issues. The fix involved replacing the damaged wiring connector and properly sealing the moisture sensor assembly. Total cost was 95 Euro, including diagnostic work and parts. The issue never returned after the repair. Before suggesting specific solutions for your case, could you share: Have you noticed any correlation between wet weather and the problem occurring? Are there any other warning lights besides the check engine light? Does the rough running happen more frequently when the engine is cold or warm? Have you had any recent work done near the engine sensors? These details would help determine if you are facing the same connection issue I experienced.

With my current mileage at 165261 KM and having just completed the latest service, I can confirm experiencing these exact symptoms. The electrical fault seemed to worsen particularly during wet conditions. After consulting with several repair shops, it turned out the sensor fault was indeed moisture-related, and replacing the sensor assembly resolved the issue. The water sensor repair cost me around 280 Euro including parts and labor. Before committing to the replacement, the shop did thorough sensor testing which confirmed the diagnosis. The engine has been running smoothly since the fix, with no reoccurrence of the check engine light. I would highly recommend getting the specific error codes checked professionally, as similar symptoms can sometimes point to different underlying issues with the engine management system.

Thanks for the update about your A8 sensor repair. Your experience matches what I encountered with my A6, these auto electronics can be tricky when moisture gets involved. The price difference between our repairs (yours at 280 Euro vs my 95 Euro) likely comes down to the more comprehensive sensor assembly replacement you needed, while mine just required connector repair. The thorough car diagnostics you had done was definitely the right approach, as these electrical fault issues can be deceptive. Its interesting that we both noticed the correlation with wet weather, this is actually a common trigger for moisture-related sensor malfunctions in these models. Since your repair included a complete sensor assembly replacement, you should be better protected against future water infiltration than my connector-only fix. Great to hear the check engine light hasnt returned. For others reading this thread who might face similar issues, the key takeaway is that proper sensor testing by professionals is crucial, even if it seems like an obvious moisture problem at first.

Thank you all for the helpful information about the moisture sensor issue. After experiencing the problem firsthand and getting it fixed, I want to close this thread with a final update for anyone facing similar symptoms. The electrical fault in my 2013 A8 has been completely resolved after the 280 Euro sensor assembly replacement. The auto electronics are now functioning perfectly, with no check engine lights or rough running for over 2000km since the repair. For anyone troubleshooting similar issues, here are the key points from my experience: Professional sensor testing was essential for accurate diagnosis, Wet weather definitely made the symptoms worse, The complete sensor assembly replacement was worth the higher cost, The rough running during acceleration completely disappeared after the fix My advice would be to not delay getting these sensor issues checked out, as they can potentially lead to more serious problems. The thorough diagnostics and proper repair have made a noticeable difference in how the car runs. Thanks again to everyone who shared their knowledge about this electrical fault issue.