28231462 — Symptoms & Failure Modes
Common symptoms and verified failure modes of a failing Delphi 28231462 1.2 TDI (CFWA) Common Rail Injector (VW Polo / Skoda Fabia-Roomster / Seat Ibiza).
Rough idle / vibration · high
A leaking injector unbalances cylinder fuelling on the 1.2 TDI.
Hard starting · high
Excess back-leakage drops cranking rail pressure.
Loss of power / limp mode · high
Out-of-range delivery or rail-pressure deviation cuts power.
Black smoke · medium
Poor atomisation over-fuels the cylinder.
Engine management light · medium
Cylinder-specific injector or fuel-metering codes.