Audi A8 Fuel Injection Fix: Expert Solutions Revealed

Having some experience with diesel engine issues, I dealt with very similar symptoms on my 2006 Audi A6 TDI. The onboard diagnostics showed fuel injection system faults, and the engine was running noticeably rough, especially during cold starts. After initial system checks, the workshop identified a faulty injector through their diagnostic equipment. The fuel economy had dropped significantly before the repair, consuming about 15% more fuel than usual. The complete fix involved: Full diagnostic scan, Removal and testing of injectors, Replacement of one defective injection valve, System reset and recalibration, Performance tuning of the injection timing Total cost was 515 Euro, including parts and labor. The repair restored normal engine performance and fuel efficiency. To provide more specific advice for your case, could you share: Current mileage, When the symptoms first appeared, Whether the rough running is constant or intermittent, Any unusual sounds or smoke from the exhaust, Previous maintenance history, especially fuel system related work This information would help determine if your issue matches what I experienced and whether similar solutions might apply.

Thanks for sharing your experience. My A8 has 151149 KM and had its last major service 6 months ago. The symptoms match closely with what you described. The rough running is most noticeable during cold starts and the airflow sensors seem to be struggling to maintain proper readings. The workshop suggests a complete fuel system diagnostic scan and possible recalibration of the injection system. They mentioned drift compensation values are out of normal range. Looking at fuel consumption logs from my onboard diagnostics, I am seeing about 12% higher usage over the past month. Has anyone else noticed similar fuel economy impacts before getting their injection system serviced?

After fixing my injector issue, I can confirm that fuel economy problems are a common symptom of drift compensation errors. My A6 showed similar consumption increases, around 12-15% higher use before the repair. The symptoms you describe match my experience exactly, particularly the cold start issues and irregular airflow sensor readings. The fuel injection system on these engines requires precise calibration, and when the drift compensation values move out of spec, it directly impacts performance. The diagnostic process used on my car revealed that the system was overcompensating for worn injector components. After the repair and system reset, the engine management computer needed a complete recalibration to restore proper fuel injection timing. The performance tuning process took about an hour as the system had to relearn proper compensation adjustment values. Since the fix, my fuel economy returned to normal and the rough running completely disappeared. Given your similar symptoms and fuel consumption data, I would recommend proceeding with the full diagnostic scan. The initial assessment costs are worth it to prevent potential long-term damage to the injection system.

Thanks for the feedback. The additional details about the diagnostic process and repair outcomes are really helpful. I scheduled the workshop visit for next week. They will perform the full fuel injection system diagnostic scan and check the drift compensation values. Based on the shared experiences here, I am more confident about proceeding with their suggested repair approach. The similarity in fuel economy impact, my 12% increase matching others experiences, suggests this is indeed a common pattern with these injection system issues. I will make sure they perform a complete system reset and recalibration of the airflow sensors after any repairs. I will update this thread once I have the final diagnosis and repair results. The workshop estimates around 500 Euro for the full service if injector replacement is needed, which seems in line with what others paid.