A5 TDI DPF Troubles: Black Smoke & Power Loss Alert

Had the same symptoms on my A4 2.0 TDI last winter. The engine light came on followed by black smoke and significant power loss. Initial diagnostics showed high backpressure readings and a sensor fault in the DPF system. First attempted DPF cleaning and forced regeneration, but the issue returned within weeks. The complete DPF unit needed replacement due to internal damage. The ceramic core had partially collapsed, making regeneration impossible. This turned out to be a serious repair requiring the exhaust system to be partially dismantled. The new DPF unit included updated sensors and mounting hardware. The repair took two full days at the shop. After replacement, engine performance returned to normal, and there have been no warning lights for 15000km. Worth noting that preventive maintenance helps avoid these issues, regular motorway drives allow proper DPF regeneration cycles and using the correct oil spec prevents ash buildup. Main advice: Get a proper diagnosis with pressure testing before deciding between cleaning or replacement. Sometimes cleaning is enough, but damaged filters need complete replacement.

Thanks for sharing your experience. I faced similar symptoms with my A5 2.0 TDI back in 2021. The DPF cleaning worked temporarily, but ended up needing a complete diesel filter replacement after two months. The fuel efficiency improved dramatically once fixed. The sensor fault warning kept coming back until the full replacement was done. My mechanic mentioned that failed regeneration cycles had damaged the filter beyond repair. Can you share how much you paid for the complete repair? Also curious if youve had any issues since the replacement or if the fix has been lasting? Might help others gauge if their quote is reasonable.

Thanks for asking about the costs. Since having the defective diesel particulate filter replaced at the mechanic, the vehicle has performed flawlessly for over 18 months. The total repair came to 1550 Euro, which included the new DPF unit, sensors, and labor costs for the exhaust system work. The vehicle inspection right after the repair confirmed that all backpressure readings were back to normal specs. No more sensor fault codes or warning lights have appeared since then. Fuel consumption has remained stable and the engine response is much better than before. Regular motorway driving has helped maintain proper DPF regeneration cycles. The investment was worth it considering the improved performance and reliability. For anyone facing similar issues, getting a complete diagnostic check is crucial before deciding between cleaning and replacement.

Thanks everyone for the insights. After getting quotes from several shops, I went with a specialist who really knew their way around exhaust system repairs. The total cost came to 1850 Euro for a complete DPF replacement including new sensors. The repair process took about 3 days total. The mechanic showed me the old diesel filter which was completely clogged and had internal damage. They also found a sensor fault that was preventing proper regeneration cycles. After six months and 12000km of driving, the fix has proven reliable. No more black smoke, backpressure issues, or warning lights. The engine feels much stronger and fuel consumption has improved significantly. The shop provided detailed diagnostics and pressure testing before and after the repair. While the cost was higher than initially hoped, the thorough work and improved performance made it worthwhile. For others facing similar issues, I recommend getting comprehensive testing done before deciding between cleaning and replacement.