0445110263 — Symptoms & Failure Modes
Common symptoms and verified failure modes of a failing Bosch 0445110263 2.1 CDI (OM646) Common Rail Injector (Mercedes Vito / Viano W639).
Rough idle / vibration · high
A leaking injector unbalances cylinder fuelling on the 2.1 CDI.
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.