P0256: Injection Pump Fuel Metering Control B (Cam/Rotor/Injector)
Do not keep driving
Expect poor power and rough running. Diesel injection specialist work — have the fault confirmed before pump replacement is proposed.
What this code means
A fault in the second fuel metering control within the injection pump. A second control appears on pumps serving more cylinders than one metering circuit can manage, or on systems that split metering between banks. Establish which cylinders this control feeds before diagnosis, since the symptom will be confined to them.
Likely causes
Start here
- Worn injection pump metering assembly · specialist
- Failed fuel metering control solenoid · specialist
- Fuel contamination · specialist
Less common
- Restricted fuel filter · easy
- Corroded or loose connector · easy
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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