Injection Pump Fuel Metering Control "A" Intermittent (Cam/Rotor/Injector)

Possible causes

• CommonFailed fuel metering control solenoid or valve
• CommonWiring or connector fault at the injection pump
• CommonWorn injection pump
• CommonLow fuel pressure, a blocked filter, or air in the fuel system
• PossibleContaminated or misfuelled diesel
• RareFailed control module driver

What you might notice

• Reduced power or limp mode
• Excessive smoke
• Hard starting or no start
• Rough running
• Engine cutting out
• Check engine light on

What to check, in order

1. Note the conditions - hot, over bumps, or when the fuel level is low. A fault that appears only with a low tank points at fuel supply rather than wiring.
2. Check the fuel filter and when it was last changed. A blocked filter starves the pump and produces metering faults with a perfectly good pump - and it is by far the cheapest thing to eliminate.
3. Check the connector and wiring at the injection pump.
4. Look for air in the fuel system, and for leaks on the suction side that would let it in.
5. Ask about recent fuelling. Contaminated or misfuelled diesel damages high-pressure pumps, and the damage spreads to the injectors.
6. Get a professional assessment before replacing the pump - it is one of the most expensive parts on a diesel and it is often blamed for supply problems upstream of it.