Q5 TDI DPF Failure Causing White Smoke During Acceleration

Last month my 2014 Audi A6 3.0 TDI showed similar symptoms. The vehicle diagnostics revealed a defective exhaust back pressure sensor, but this was only part of the issue. The faulty pressure sensor caused incorrect readings, leading to incomplete DPF regeneration cycles. However, inspection showed the DPF was severely clogged, creating excessive back pressure in the exhaust system. The vehicle emissions were affected because the system couldn't properly measure and regulate exhaust flow. This required both sensor replacement and DPF cleaning to restore proper engine performance. The repair involved: Replacing the exhaust pressure sensor, Professional DPF cleaning, Resetting the engine management system, Running forced regeneration cycles This was a serious issue requiring immediate attention, as continued driving could have led to complete DPF failure and potential engine damage. The white smoke during acceleration typically indicates trapped particles not burning off properly during regeneration cycles. Based on your symptoms, recommend getting both the pressure sensor and DPF system checked. These issues often occur together and addressing just one component might not solve the underlying problem.

Thanks for sharing your experience with the A6. I had nearly identical issues with my Q5 last year. Did the repairs fully resolve the problems for you? Curious about the total cost since I paid 1200 Euro for similar work on my vehicle diagnostics and exhaust system maintenance. The auto repair shop also mentioned I should consider regular DPF cleaning to prevent future clogging, have you needed any follow-up service since the initial fix?

The repair work fully resolved all problems with my A6. The mechanic confirmed the main culprit was the exhaust back pressure sensor malfunction, which they fixed last week for 245 Euro. The vehicle diagnostics accurately pinpointed this as the root cause. Since the car maintenance was completed, no white smoke issues during acceleration and the DPF regeneration cycles run perfectly. The pressure sensor readings are now stable and accurate, which has improved overall exhaust system performance. As for regular DPF cleaning, I have not needed any follow-up service yet. The mechanic suggested monitoring the car maintenance status through the vehicle diagnostics system and scheduling DPF cleaning only when the system indicates its necessary, rather than at fixed intervals. This approach seems more cost-effective while still ensuring proper exhaust system function. Your 1200 Euro repair cost seems quite high compared to just replacing the faulty sensor. Perhaps your DPF required more extensive cleaning or additional components needed replacement. Regular monitoring of pressure sensor readings through basic vehicle diagnostics can help catch issues early before they lead to costlier repairs.

After taking the Q5 to my trusted mechanic last week, my exhaust system issues are finally resolved. The repair process went smoother than expected. A thorough vehicle diagnostics test confirmed both a faulty pressure sensor and partially clogged DPF were causing the problems. The total repair cost came to 890 Euro, which included: New exhaust sensor installation, DPF cleaning service, System recalibration The engine performance has significantly improved since the repair. No more white smoke during acceleration and the DPF warning light remains off. The mechanic suggested checking the exhaust back pressure readings every 6 months to prevent future issues. While this wasnt a cheap fix, its far better than risking complete DPF failure. The vehicle emissions are now within normal range and regeneration cycles complete as they should. Glad I addressed this early before it led to more extensive damage.