TDI Injection Issues: Fix Guide and MPG Impact

I had almost identical issues with my 2011 Golf TDI. As someone with moderate experience working on diesel engines, I first attempted a system reset through onboard diagnostics, but the check engine light kept returning. The symptoms matched yours exactly, rough running and drift compensation errors. After monitoring fuel consumption for a week, I noticed it had increased by about 15%. The workshop diagnosed a faulty injector in cylinder 2. They performed: Complete injector removal and testing, Replacement of the defective injection valve, Reset of the drift compensation values, Recalibration of airflow sensors, Full system diagnostic scan Total repair cost was 515€ but the improvement was immediate. Idle smoothed out completely and fuel economy returned to normal. Which error codes specifically are you getting? Would be helpful to know: Your current fuel consumption, Whether idle is rough or only under load, If you notice any smoke from exhaust, Current mileage on the vehicle This would help determine if you are facing the same injector issue or possibly something else in the fuel system.

Had mine fixed last month at 28734km. After repair, the rough running completely disappeared and no CEL since then. Car sensors and performance tuning were checked during service. The onboard diagnostics now show all clear, with fuel economy back to normal levels, getting about 5.8L/100km on average. Money well spent for proper injector repair and calibration. Makes sense to get it fixed professionally rather than trying temporary fixes.

Thanks for the update on your Jetta repair. Glad to hear you got similar positive results to what I experienced with my Golf TDI. The improvement in fuel economy to 5.8L/100km matches what I saw after my repair, these engines really perform efficiently when the injection system is properly calibrated. The professional repair approach definitely made sense rather than attempting temporary fixes. My fuel economy has remained stable for 6 months now since the repair, and the car sensors continue to show normal readings. One tip from my experience: I recommend keeping an eye on the fuel consumption through the onboard computer. Any sudden changes could indicate early drift compensation issues before they become serious enough to trigger the check engine light again. Good to know the performance tuning and calibration cleared up your rough running issues completely. These TDIs are solid engines when the injection system is working correctly.

The car is running great after the fix, no more rough running or warning lights. Professional repair was definitely worth it since they properly reset the compensation adjustment values and recalibrated everything. The onboard diagnostics are all clear now and fuel economy is back to normal at 5.8L/100km. The shop did a thorough job testing the fuel injection system and car sensors. Much better to get it done right with proper equipment than try quick fixes. Seems others had similar positive results after professional injector repairs and calibration. Should be good to go for many more kilometers now that everything is tuned correctly. I will keep monitoring the consumption readings from here to catch any early signs of drift. Really happy with how the repair turned out overall.