Operating a fuel injector in a fuel system for an engine includes energizing a first solenoid actuator to move a spill valve from a first position to a second, closed position, and energizing a second solenoid actuator to move a fuel injection valve in the fuel injector from a closed position to an open position. A pull-in tier of a waveform energizing the second solenoid actuator is generated via a first current produced by a boosted voltage power supply and a second current produced by a lower voltage power supply. Arrival timing of the valve at the open position is detected based on a property of the second current, such that a valve arrival timing error may be used to trim the fuel injector. Related methodology and control logic is also disclosed.

An electromagnetic actuator includes an electrical coil and a high permeability magnetic flux path. The magnetic flux path includes a magnetic core, an armature and a flux return structure. The electromagnetic actuator further includes a flux sensor which is integrated within the actuator and is configured to detect a magnetic flux within the high permeability magnetic flux path.

An apparatus for closed loop operation of a solenoid-activated actuator includes an external control module and a power source which are electrically and operatively coupled to an activation controller of the actuator. The external control module and the power source are located externally to the actuator. The apparatus further includes an activation controller which is integrated within the body of the actuator. The activation controller includes a control module and an actuator driver and is configured to communicate with the external control module and to receive electrical power from the power source. The apparatus additionally includes at least one sensor device which is integrated within the body of the actuator and is electrically and operatively coupled to the activation controller. The at least one sensor device is configured to measure one or more parameters during operation of the actuator and the measured parameters are provided as feedback to the activation controller.

Operating a fuel injector in a fuel system for an engine includes energizing a first solenoid actuator to move a spill valve from a first position to a second, closed position, and energizing a second solenoid actuator to move a fuel injection valve in the fuel injector from a closed position to an open position. A pull-in tier of a waveform energizing the second solenoid actuator is generated via a first current produced by a boosted voltage power supply and a second current produced by a lower voltage power supply. Arrival timing of the valve at the open position is detected based on a property of the second current, such that a valve arrival timing error may be used to trim the fuel injector. Related methodology and control logic is also disclosed.