A black smoke(Soot) is discharged through muffler at accelerating, and poor acceleration occurs or poor power occurs rapidly.

▶ Inspect DPF(blocked, damaged) visually after removing.

Lots of white smoke is discharged continuously/intermittently when DPF temperature is higher than 600℃ or in the DPF regeneration mode or in the forcing DPF regeneration function.

▶ The excessive sulfur to be contained at the fuel can be the reason. Replace all fuel and verify that the symptom is corrected.

A small quantity of black smoke(Soot) is discharged through muffler when engine is accelerated, there is no trouble symptom.

▶ There is small crack or broken of DPF in the DPF assembly after removing.

Inspect that ECM/PCM has the right IQA code written on the surface of each injector by scantool.

Inspect carbon deposit/damage/blocked/widen hole of the injector nozzle after remove the injector.