0445110255 — Symptoms & Failure Modes
Common symptoms and verified failure modes of a failing Bosch 0445110255 1.5 CRDi (D4FA) Common Rail Injector.
Hard starting / extended cranking · high
Injector back-leakage drops cranking rail pressure on the 1.5 CRDi, making the engine slow to start, especially cold.
Rough idle and vibration · high
A worn or leaking injector unbalances cylinder fuelling, producing a shaky, uneven idle.
Black smoke · medium
Poor atomisation from a worn nozzle or ball-seat erosion over-fuels the cylinder.
Loss of power / limp mode · medium
Out-of-range injector delivery triggers reduced performance or limp mode on the D4FA.
Check-engine light (MIL) · medium
Cylinder-specific injector or rail-pressure fault codes stored in the ECU.
Increased fuel consumption · medium
Over-fuelling or internal leakage wastes fuel and can fail emissions.