074130202B — Symptoms & Failure Modes
Common symptoms and verified failure modes of a failing Bosch 074130202B 2.5 TDI Nozzle-Holder Injector (VW Transporter T4).
Rough idle / vibration · high
A leaking or out-of-calibration injector unbalances cylinder fuelling, felt as a shake at idle.
Hard starting · high
Excess back-leakage bleeds rail/line pressure during cranking, causing long or failed starts.
Loss of power / limp mode · high
Out-of-range delivery or pressure deviation triggers a torque cut and limp home.
Black smoke · medium
Poor atomisation or a dribbling nozzle over-fuels the cylinder.
Engine management light · medium
Cylinder-specific injector, balance or fuel-metering fault codes are logged.