VW Lupo Diesel: Fixing Quantity Drift Compensation

I had almost the exact same issue with my 2003 VW Polo TDI. As someone who does basic maintenance but leaves complex issues to professionals, this problem caught me off guard. The symptoms matched perfectly, rough running, check engine light, and drift compensation errors. After attempting a basic system reset which didnt help, I took it to a workshop. Their diagnostic equipment showed one injector was consistently misfiring. The repair process involved: Full diagnostics and injector testing, Replacing the faulty injector, Car sensors recalibration, Performance tuning adjustment, Complete drift compensation reset procedure Total cost was 515€, which included parts and labor. The fix completely resolved the rough running and the engine light hasnt returned since. For a more specific assessment of your case, could you share: Current mileage, When the problem first appeared, Whether performance drops noticeably under load, If there are any cold start issues, What error codes your system shows This information would help determine if your Lupo is experiencing the same injector-related problems I encountered.

Just had my service last week, so the data is fresh. After checking the onboard diagnostics, I found these exact symptoms in my Lupo. The rough running started gradually, especially noticeable during cold starts. The engine management light came on shortly after. My fuel economy dropped significantly, and the engine felt sluggish under load. I noticed the airflow sensors readings were inconsistent when using my basic diagnostic tool. The fuel injection system seems to require a professional reset, as basic attempts to clear the codes failed. The error codes point to P1403 and P0401, which align with your diagnosis of injector issues. Good to know your repair path worked, might have to budget similarly for the fix.

Thanks for providing those error codes, they actually match what I saw in my Polo before the repair. The P1403 and P0401 combination definitely points toward the fuel injection system, just like in my case. The inconsistent airflow sensor readings you mentioned are a classic sign of the problem I experienced. Speaking from my repair experience, the compensation adjustment issues got worse over time, especially affecting cold starts. I first tried clearing the codes too, but like you found, the basic resets did nothing permanent. The professional diagnostic showed that the drift compensation values were way off normal range. The sluggish performance and poor fuel economy match exactly what I dealt with. After the complete repair with new injectors and proper performance tuning, my fuel consumption returned to normal and the cold start issues disappeared completely. Worth mentioning that when they did my repair, they found the car sensors needed a full recalibration after the injector replacement. This extra step was crucial for the drift compensation reset to work properly. If the symptoms are this similar, you might want to expect repair costs around what I paid (515€). The investment was worth it, the engine has run smoothly for over a year now with no warning lights.

The professional advice matches my situation perfectly, those exact error codes and symptoms in my Lupo. The gradual onset of rough running and cold start issues, combined with the engine management light, suggests I'm dealing with the same injector-related problems. The onboard diagnostics from my recent service showed similar drift compensation values being out of range. My fuel economy has definitely suffered, dropping about 15% from normal. The engine continues feeling sluggish under load, and like they mentioned, basic system reset attempts haven't fixed the stored error codes. Given the matching error codes P1403 and P0401, plus the inconsistent airflow sensor readings, I'll probably need the full repair procedure they described. Their 515€ repair cost gives me a good benchmark for budgeting. The comprehensive fix, including new injectors, performance tuning, sensor recalibration, and proper reset procedures, seems worth the investment to restore normal operation. I'll schedule an appointment with a shop that has the right diagnostic equipment for VW injection systems. Good to know the repair should resolve both the check engine light and rough running issues completely.