VW Atlas Stalling: Bad Fuel Leads to Engine Troubles

I had a similar issue with my 2015 VW Tiguan. With some experience working on VWs, I can share what worked for me. The symptoms you describe could be related to the fuel mixture or a faulty connection. In my case, the engine knock and stalling were caused by a loose connection in the wiring harness leading to the fuel injection system. After adding fuel additives and replacing the fuel filter without success, my mechanic found the actual issue was a damaged plug connection to the fuel pressure sensor. The repair involved cleaning the connector pins and replacing the damaged wiring section, costing 95€ including diagnostic time. This completely resolved the stalling and error codes. Before assuming fuel contamination in the combustion chamber, we should rule out electrical issues. Could you share: Current mileage, Specific error codes stored, When exactly the problem started, Does it happen only when the engine is warm or cold, Any other symptoms besides stalling Using wrong fuel or contaminated fuel usually shows different symptoms, but knowing these details would help narrow down the cause.

Thanks for the detailed reply. My mileage is exactly 123977km and I just had the car serviced last month. The error codes point to a fuel delivery problem, but your insight about checking the wiring connections makes sense. I notice the stalling happens more when the engine is warm, especially after driving in stop and go traffic. The engine knock is most noticeable during acceleration. Besides these issues, I also notice a slight hesitation when pressing the gas pedal. I will have my mechanic inspect the wiring harness and connectors to the fuel system components. Good to know that cleaning and replacing damaged wiring resolved similar symptoms in your case. Perhaps the combination of questionable fuel quality and a loose connection is creating these issues. I will report back once we identify the root cause.

Your experience matches my findings exactly. Since we have identical symptoms on our VW engines, I can confirm it was not just the wiring in my case. After further diagnosis, we found the fuel filter was partially clogged, reducing proper fuel delivery to the combustion chamber. The hesitation during acceleration combined with warm engine stalling strongly suggests restricted fuel flow. When I replaced both the wiring and the fuel filter, the fuel economy improved noticeably and all symptoms disappeared. The total repair ended up being 180€, higher than initially quoted but worth it to resolve the fuel mixture issues completely. The fuel filter was quite dirty, likely from a combination of regular wear and possibly that questionable fuel. Given your mileage and the fact these issues appeared after using unknown quality fuel, I would recommend: 1. Replace the fuel filter 2. Check all fuel system connections 3. Run a complete fuel system cleaning 4. Add a quality fuel system cleaner to your next few tanks This comprehensive approach should resolve the stalling and hesitation issues, just as it did in my case.

Thanks for the follow up and seeing similar symptoms in your VW. The error codes stored are P0171 and P0087 which do point to fuel delivery problems like you mentioned. Looking at my current situation, I think the combination of potentially contaminated fuel and the restricted fuel flow through a clogged filter makes the most sense. The fuel economy has definitely gotten worse lately which supports this theory. The warm engine stalling in traffic and hesitation during acceleration match exactly what you experienced. I will schedule an appointment to have them perform the complete fuel system service you suggested, including replacing the fuel filter and checking all connections. The 180€ cost seems reasonable considering it solved the issues completely in your case. I will make sure they inspect the wiring harness as well since loose connections could be contributing to the problems. I appreciate you sharing the comprehensive repair approach that worked. Will pick up some quality fuel system cleaner today to start addressing any contamination. Once I get all the work done, I will avoid that questionable fuel station in the future to prevent similar issues. Thanks again for helping narrow down the likely cause.