VW Polo TDI Rough Running Fixed via Injection Reset

Dealt with a similar issue on my 2014 VW Golf TDI. After seeing your symptoms, it sounds nearly identical to what I experienced. The onboard diagnostics also showed drift compensation issues. Started with rough idling and inconsistent acceleration. The fuel economy dropped significantly, which was the first red flag. After an initial system reset failed to resolve the issue, the workshop diagnosed a faulty fuel injection valve on cylinder 2. The repair included: Complete injector removal and testing, Replacement of one defective injector, Full system reset and calibration, Performance tuning to ensure proper fuel delivery Total cost came to 515€, including parts and labor. The repair completely resolved the unstable running and restored normal operation. Before suggesting specific solutions, could you share: Current mileage, When was the last fuel filter change, Are you using any fuel additives, Does the rough running vary with engine temperature, Exact error codes from your scan This information would help determine if your issue mirrors what I encountered or if other components might be involved.

Just had my 13705km service last week. The fuel filter was replaced during the last major service. After reviewing your repair details, my symptoms match exactly what you described. The car performance drops significantly during cold starts, and the rough running is most noticeable when the engine is warming up. The car sensors are showing P0101 and P0401 codes during drift compensation checks. The onboard diagnostics also indicate similar injection timing issues. At this point, having this data helps confirm it might be the same injector problem. Planning to bring it to the workshop for a thorough system reset and injector inspection before considering a full replacement.

Thanks for the additional details. Based on my Golf TDI experience, those error codes combined with the cold start issues strongly point to injector problems. The P0101 and P0401 codes typically indicate air flow and EGR issues, but in my case, these were secondary symptoms caused by the faulty injector throwing off the fuel injection timing. Since you mentioned cold start problems, this matches exactly how my issues progressed. The onboard diagnostics initially misled our workshop to focus on airflow sensors, but the root cause was the injector. Quick tip from my repair: have them check the injector return flow rates during the diagnostic. My faulty injector showed excessive return flow, which confirmed the diagnosis before replacement. This test saved time rather than jumping straight to a full system reset. Some key factors that were checked in my repair: Individual injector performance values, Return flow measurements, Fuel pressure during cold starts, Drift compensation values across all cylinders The full repair resolved both error codes and restored proper fuel economy. Given your similar symptoms and codes, requesting a complete injector diagnosis before any system reset would be the most efficient approach.

Thanks for sharing those repair insights. My situation really does mirror your Golf TDI experience, especially with those specific symptoms during cold starts. Given that both the drift compensation values and error codes match your case, I feel more confident now about the likely injector issue rather than just sensor problems. Will definitely ask the workshop to start with injector return flow testing before attempting any system reset procedures. The fuel injection diagnostic steps you outlined make a lot of sense, especially checking the individual cylinder performance values. Good to know the repair solved both the error codes and restored proper fuel economy in your case. I have scheduled a workshop visit for next week. Will make sure they check all those key diagnostic points you mentioned, particularly the injector performance during cold starts. Hoping the repair cost stays around the 515€ mark like in your case. This has been really helpful in understanding what to expect during the diagnostic and repair process.