Audi S5 DPF Crisis: Sensor Triggers Multiple Issues

Similar issue occurred on my 2019 Audi S4 diesel. With some experience in auto repair and car maintenance, I can share what worked for me. The symptoms matched exactly, check engine light, dark smoke, and DPF issues. After scanning, the exhaust back pressure sensor was identified as faulty, affecting overall engine performance. My workshop followed these steps: 1. Full diagnostic scan 2. Pressure sensor signal testing 3. Physical inspection of sensor connections 4. Back pressure measurement validation The fix involved replacing the defective pressure sensor and resetting the engine management system. Total cost was 245 Euro including parts and labor. After replacement, DPF regeneration returned to normal and smoke issues disappeared. To provide more specific guidance for your case, could you share: Current mileage, Any recent maintenance work, Specific error codes from scan, When DPF was last serviced, Any performance changes noticed before these symptoms These details would help determine if your S5 is facing the exact same sensor issue or if additional components need inspection.

Thanks for sharing your experience. My S5 just had its scheduled service last month at 9376 KM. I ran a diagnostic scan showing error codes P0472 and P2002, both linked to the exhaust pressure system. Unlike other cases, I have not noticed any significant power loss, but the emission control system seems compromised given the DPF behavior. Considering the vehicle age and low mileage, a faulty sensor does sound like the most logical explanation, matching your experience with similar symptoms.

Thanks for providing those details. Your error codes confirm what I experienced with my S4, they are typical indicators of exhaust sensor issues affecting the exhaust system performance. The P0472 specifically points to low pressure input from the sensor, while P2002 indicates DPF efficiency below threshold, exactly what I encountered before replacing my sensor. The exhaust back pressure sensor is critical for proper DPF regeneration cycles. Your recent service and low mileage further support the sensor fault theory, as structural exhaust system issues would be unusual at this stage. In my case, despite similar codes and symptoms, there was no permanent damage to other components because the issue was caught early. The repair cost might vary slightly from my 245 Euro case since parts prices have changed, but the diagnostic process should be identical: Verify sensor signal readings, Test wiring connections, Replace pressure sensor, Reset control module, Confirm DPF regeneration cycle Would recommend getting this addressed soon, as continuing to drive with a malfunctioning pressure sensor could eventually impact vehicle emissions performance and potentially lead to more costly repairs.

Good to hear this level of detail. Since my vehicle is still under warranty with such low mileage, I will take it to the dealer armed with this information about the exhaust back pressure sensor. The matching error codes and similar symptoms give me confidence about the likely root cause affecting the vehicle emissions system. Will have them focus on the pressure sensor during their vehicle diagnostics rather than jumping to more extensive repairs. The fact that your fix resolved both the DPF regeneration and smoke issues is encouraging. Thanks for breaking down the diagnostic steps they should follow. I will update once I get the repair completed in case it helps others with similar engine performance problems.