Audi A4 TDI Power Loss & Smoke: DPF Warning Signs

Had nearly identical symptoms with my Audi A6 2.0 TDI from 2015. The power loss during acceleration and smoke were clear indicators of DPF problems, confirmed by vehicle inspection at an independent specialist shop. The backpressure test showed a severely clogged DPF. DPF cleaning was attempted first but proved ineffective due to excessive soot buildup. Filter replacement became necessary as the regeneration cycles had failed multiple times. The exhaust system inspection revealed the DPF sensors were also compromised, contributing to the failed regeneration attempts. This explained why the engine management light kept triggering. The repair involved: Complete DPF filter replacement, New pressure sensors, Recalibration of the engine management system It was a serious issue requiring immediate attention, as continuing to drive risked further engine damage. Getting it fixed at a specialized diesel workshop proved more efficient than previous dealer experiences. They had proper diagnostic equipment and DPF-specific expertise. Your symptoms match a clogged DPF, but recommend getting the entire exhaust system checked. Sometimes upstream issues like EGR problems or incorrect oil specs can cause similar symptoms.

Thanks for the detailed response about your A6 repair. I had similar problems with my A4 about 8 months ago. The fuel efficiency dropped dramatically and the engine light kept coming on. After multiple failed regeneration attempts, I also needed a complete DPF replacement. Would you mind sharing what you paid for the full repair? In my case, there were additional sensor faults that needed fixing, which drove up the total cost. Curious if anyone else faced extra issues after the DPF work was done?

Since getting my Audi serviced, the DPF problems have been completely resolved. The total repair came to 1550 Euro, which covered the full replacement of the defective diesel particulate filter along with new sensors and system calibration. The fuel efficiency has improved significantly and there have been no recurring sensor faults or engine light warnings. The exhaust system is working perfectly now with proper backpressure levels, and regeneration cycles are completing normally. Unlike some others, I was fortunate not to experience any additional issues after the DPF work. The specialist shop did a thorough job diagnosing and fixing all related components at once. Their comprehensive approach, while expensive, prevented any follow-up problems. I can now confirm they fixed the root cause rather than just treating symptoms, as the car has been running smoothly for several months with no power loss or smoke issues during acceleration.

After seeing all these responses about DPF issues, I finally got my A4 fixed last week. Went to a specialized diesel workshop after researching several options. The diagnostic confirmed a completely clogged diesel filter and faulty sensors. The total bill came to 1850 Euro including: New DPF, Pressure sensors, System recalibration, Labor costs More expensive than expected but worth it. The fuel efficiency has improved dramatically and the engine light is finally off. No more power loss or smoke during acceleration. The backpressure readings are now normal and the regeneration cycles are working properly. One tip: They found my air filter was also quite dirty, which apparently contributed to the DPF issues. Getting that replaced as preventive maintenance saved potential future problems. Really glad I addressed this properly instead of trying cheaper temporary fixes. The car runs like new now, and the repair shop provided a 2-year warranty on the work.