Audi S7 Stalling: Fuel Regulator vs. Hidden Causes

Having some experience working on Audis, I faced a similar issue with my 2021 Audi S6. The symptoms you describe match exactly what I encountered, rough idle, stalling, and reduced power, along with the check engine light. After multiple fuel efficiency tests, my workshop diagnosed a defective high pressure fuel pump, not just the regulator. The pump failure was causing irregular fuel delivery, leading to those performance issues. The repair included replacing the entire high pressure pump assembly, which ended up costing 1510 Euro including parts and labor. For proper automotive repair diagnosis, could you share: Current mileage, Fuel type used, Any recent car maintenance performed, Whether car sensors are showing any specific error codes, If the issue occurs more during cold starts or warm engine The S7 and S6 share many components in their fuel delivery systems, but pinpointing the exact cause requires these details. Getting the right diagnosis is crucial for fuel economy and long-term reliability. Would suggest having a full diagnostic scan done before any repairs, as similar symptoms can sometimes stem from different root causes in these engines.

Just had my car maintenance done at 174780 KM. The workshop pulled the error codes and confirmed the issue is fuel delivery related. Have been using premium 98 octane since new and no previous issues until now. The problem happens consistently regardless of engine temperature. Would definitely appreciate a more detailed breakdown of your repair process and any preventive measures for fuel system maintenance going forward.

Thanks for those details. After my S6 repair, Ive put another 50000km on it with no recurring issues. The fuel delivery problem ended up being more complex than initially thought, the high pressure pump had damaged the fuel pressure sensor and regulator due to metal debris circulation. The complete repair process included: High pressure fuel pump replacement, Fuel pressure sensor replacement, Fuel system cleaning, New fuel filter, Updated ECU calibration The automotive repair took about 2 days total. A key learning was that these pumps can deteriorate without obvious warning signs until they fail. For preventive maintenance, I now: Change fuel filters every 30000km instead of the recommended 60000km, Use fuel system cleaner every 10000km, Monitor fuel efficiency through the car computer for any unexpected changes Your symptoms being consistent across temperatures actually matches my experience perfectly. The rough idling and power loss were also constant in my case. The car sensors should show specific pressure-related codes that can confirm if your issue is identical to what I experienced. Total cost breakdown for reference: Parts: 1100 Euro, Labor: 410 Euro, System cleaning and calibration: 180 Euro Consider getting the fuel filter changed during repairs even if not due, it provides good insurance against any debris in the system.

As the original questioner, I appreciate the detailed breakdown of your repair experience with such similar symptoms. Really helps to have real-world cost figures and the complete repair process outlined. Your preventive maintenance schedule makes a lot of sense, especially the more frequent fuel filter changes. I was concerned about potential metal debris causing cascade failures, so knowing the full scope of your repair gives me a much clearer picture of what to expect. Since our symptoms match so closely and we have similar fuel injection systems, I will definitely have the workshop check the high pressure pump and related components. The total repair cost you provided of 1690 Euro is actually lower than I feared for this level of work. Getting the fuel filter done during repairs seems like smart preventive maintenance. Will schedule the repair next week and make sure to implement your suggested maintenance intervals for better fuel system care. Understanding that the car sensors might show pressure-related codes will help me better communicate with the workshop about the diagnosis.