VW Passat Diesel: Fuel Injection Drift Fix Guide

I dealt with nearly identical symptoms on my 2021 VW Arteon TDI last year. Since I have some experience with diesel injection systems, I recognized the signs immediately. The onboard diagnostics showed similar drift compensation errors. Initially, my workshop tried a system reset and recalibration of the injection parameters, but the check engine light returned within days. After a more thorough diagnosis using specialized diagnostic equipment, they found one faulty injector that was causing irregular fuel delivery. The erratic spray pattern was throwing off all the compensation values. They replaced the defective injection valve and performed a complete calibration of the injection system, which cost 515€ total. The repair resolved both the rough running and the error codes. The car has been running smoothly since then, with normal drift compensation values. Could you share: Current mileage on your Passat, When the symptoms first appeared, Whether the rough running is constant or only under specific conditions, Any fuel system maintenance history This information would help determine if your case matches what I experienced and whether you might be dealing with similar injector issues rather than just sensor calibration problems.

Had my Passat serviced last week and already seeing the exact same drift compensation issues. Going by the diagnostic report, I also tried resetting parameters through the onboard diagnostics system to improve fuel economy, but got nowhere. My fuel injection recalibration from last service was supposedly fine, but maybe they missed something. Good point about checking individual injectors, I will get that looked at since the symptoms match perfectly. Going to schedule a full diagnostic scan focusing on the injection system. Hope its not too expensive to fix. Will post updates once I know more.

Thanks for the update on your Passat situation. Those recurring drift compensation issues can be really frustrating, especially right after a service. My Arteon experience taught me that partial fixes often dont solve the underlying problem. The fact that your symptoms returned so quickly after the parameter reset suggests your issue might indeed mirror what I encountered with the faulty injector. The onboard diagnostics system can mask individual injector problems by continuously trying to compensate for irregular fuel delivery patterns. When my workshop did the full diagnostic scan, they used specialized equipment to measure the actual injection quantities versus the compensation adjustment values. This revealed the specific injector that was causing the fuel system to constantly readjust its parameters. Since youre dealing with similar symptoms, I would recommend: Having them specifically test individual injector performance, Getting a complete fuel injection system pressure test, Checking if airflow sensors are providing accurate readings The full repair cost might be similar to what I paid (515€), but catching it early usually prevents additional fuel system damage. Regular adjustment attempts through system reset alone probably wont fix this if theres an actual hardware issue like in my case.

Based on your description of the faulty injector scenario, I will definitely have them perform individual injector testing. The symptoms are matching up too closely to ignore, and these repeated compensation adjustment issues are becoming a real headache. Called my regular workshop and booked a full diagnostic session for next week. Made sure to request the specialized testing equipment for measuring actual injection quantities. The car sensors have been throwing consistent errors, so I want them to do a complete evaluation of the fuel delivery system. The possible 515€ repair cost is steeper than I hoped, but better to fix it properly now than risk more expensive damage. I will update the thread once they complete the diagnostics and confirm whether its also a bad injector causing my drift compensation problems. Thanks for sharing your experience, it helped narrow down where to focus the investigation.