Audi S5 Engine Stalling: Fuel Regulator Alert

Speaking from some experience with automotive repair, I had a very similar issue with my 2014 Audi S4 last year. The symptoms you describe match exactly what I encountered, engine misfire, reduced power, and constant check engine light. After initial diagnosis, the workshop found the high pressure fuel pump was defective, which was causing inconsistent fuel injection and affecting engine performance. The repair included replacing the pump and running extensive tests to ensure proper fuel efficiency was restored. Total cost came to 1510 Euro including parts and labor. However, these symptoms could indicate various issues, and proper diagnosis is crucial. Before proceeding, could you share: 1. Any specific error codes from the check engine light? 2. Does the problem occur more during cold starts? 3. Have you noticed any unusual fuel consumption? 4. Are there any unusual sounds when the engine is running? 5. How many miles/kilometers are on the car? Car sensors can pick up multiple issues that present similar symptoms, so having this information would help narrow down whether your problem matches what I experienced with my S4. The fuel injection system is complex, and accurate diagnosis is essential before any repairs.

Just had my last service at 52000 KM where they did a full inspection and fuel injection system cleaning. Before jumping to conclusions about the fuel volume regulator, check the fuel pressure sensor readings. My mechanic found that car sensors were picking up incorrect pressure values, leading to similar symptoms. The diagnostic process revealed a much simpler and cheaper fix, just a faulty sensor connection that was disrupting proper fuel efficiency. Would definitely recommend getting the error codes checked first before any major repairs.

Thanks for sharing your experience. The fuel pressure sensor reading issue you mentioned makes a lot of sense. On my S4, I initially also thought it was the fuel volume regulator, but proper diagnostics helped avoid unnecessary repairs. Since my earlier post, I actually discovered that car maintenance records can be crucial for accurate troubleshooting. In my case, the recent fuel injection system cleaning made it easier to rule out carbon buildup as a cause for the engine misfire and stalling issues. Your suggestion about checking error codes first is spot on. When dealing with check engine warnings and fuel system problems, starting with sensor diagnostics often reveals simpler issues. The fuel pressure sensor on these engines is known to cause similar symptoms when failing. Have you noticed any improvement in fuel economy since fixing the sensor connection? My repair costs were significantly higher because I jumped to conclusions about needing major components replaced. Going straight for sensor diagnostics could save others from making the same costly mistake. For reference, the sensor replacement and recalibration on my S4 would have only cost about 300 Euro compared to the 1510 Euro I spent on unnecessary parts.

Additional information from my experience might be helpful. Turns out I jumped the gun worrying about the fuel volume regulator. The error code scan showed P0190 which pointed to the fuel pressure sensor. The rough idling and stalling were indeed caused by incorrect pressure readings, not a mechanical issue with the fuel system. After the sensor fix, fuel efficiency returned to normal and the engine misfire issues completely disappeared. Total repair cost was 285 Euro including diagnostic time. Much better than the potential 1500 Euro+ for replacing major components. The automotive repair shop also checked my recent service records which helped rule out maintenance-related causes quickly. Car maintenance history really does make a difference in accurate diagnostics. Definitely learned my lesson about getting proper diagnosis before assuming worst-case scenarios. Would recommend anyone with similar symptoms to start with basic sensor checks before considering more extensive repairs. A failing sensor can mimic more serious fuel system problems.