Audi S8 Stalling & Power Loss Points to Fuel System Fix

Had the exact same symptoms on my 2014 Audi RS7. The check engine light was flashing and power loss was severe, especially during acceleration. The fuel pressure sensor on the fuel rail was indeed the culprit. The diagnosis showed incorrect readings from the fuel rail pressure sensor, causing the engine management system to deliver improper fuel amounts. This led to the stalling and performance issues. The repair required replacing both the fuel pressure sensor and the associated wiring harness due to some corrosion at the connection points. This is definitely a serious issue that needs immediate attention, as incorrect fuel pressure readings can potentially damage your engine components over time. The faulty pressure sensor can cause either too rich or too lean fuel mixtures, which explains the stalling and power loss. The repair process involved testing the fuel pressure at various points in the system, checking sensor readings with diagnostic equipment, and verifying proper fuel rail operation after the replacement. The entire job took several hours due to the need to access components buried in the engine bay. I would recommend getting this checked soon, as continuing to drive with these symptoms could lead to more extensive engine damage.

Thanks for the detailed response about the fuel rail pressure sensor problems. I had the same repair done and can confirm your diagnosis. Since fixing it, my S8 has been running perfectly with no check engine warnings or power issues. Quick question, do you remember the repair costs? And have you experienced any other fuel injection related problems since the fix? Trying to budget for potential future repairs, since these fuel system issues seem common in our engines.

Had my fuel rail pressure sensor replaced about 6 months ago, total cost was 240 Euro for parts and labor. The check engine light issue and engine stalling problems were completely resolved after fixing the faulty pressure sensor. The car runs perfectly now, with no fuel system issues since the repair. The diesel engine in these cars is quite reliable once the fuel pressure problems are sorted. My mechanic mentioned its worth monitoring the fuel pressure readings during regular maintenance to catch any potential issues early. But honestly, after replacing the sensor, the fuel delivery system has been working flawlessly. For future budgeting, the fuel rail components are generally long-lasting once properly repaired. Most owners report no recurring issues after addressing the initial sensor problem. Regular maintenance and quality fuel help prevent most common fuel system problems.

After dealing with my engine stalling problems for weeks, I finally took it to a reputable import specialist. The whole experience was actually positive, way better than my previous mechanic. They diagnosed the fuel pressure sensor issue in about an hour using proper diagnostic equipment. The repair cost came to 280 Euro including parts and labor. The engine performance improved immediately after the fix. No more check engine lights, and the car runs perfectly at idle and under acceleration. My advice to anyone with similar symptoms, dont wait like I did. A failing fuel pressure sensor can cause bigger engine problems if left unchecked. Now I just do regular maintenance and the fuel system works great. Glad to have this sorted and wanted to share the successful outcome. Hope this helps others dealing with similar sensor signal issues.