P0251Injection Pump Fuel Metering Control A (Cam/Rotor/Injector)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- These codes cover the electrically controlled fuel metering actuator on a diesel injection pump. On older distributor pumps it was a solenoid that set the injected quantity; on common rail it is usually an inlet metering valve on the high-pressure pump that lets only as much fuel into the pumping elements as the rail needs, instead of spilling the excess through a pressure valve. Manufacturers use different codes for this part: Ford P0001–P0004, GM Duramax P0090–P0092. P0251 is the general circuit fault of actuator A. Saab's 2011 9-5 diesel uses it for an open circuit of the pressure regulator on the high-pressure pump: if the control wire does not show the expected voltage with the driver off for more than 1 s, the code sets with the warning light at once. Depending on the system, rail pressure and power are then limited.
- What you may notice
- Check engine light on
- Loss of power, limp mode
- Rough idle or hunting
- Hard starting or stalling
- Likely causes
- LikelyMetering actuator coil open
- LikelyConnector at the actuator corroded or loose, broken wire
- PossibleSupply voltage to the actuator missing
- PossibleDistributor pump: internal electronics or quantity valve faulty
- RareDriver stage in the engine module faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.