A fuel injection controller has terminals which can be connected to the coil of the fuel injector. A first valve-open control portion supplies the valve-opening voltage to the terminals for opening the fuel injector. The first valve-open control portion stops supplying the electric supply to the coil before the fuel injector is positioned at a full-open position. Before the fuel injector is fully closed, a small injection quantity can be obtained. A demagnetization portion forms a demagnetization circuit for demagnetizing the magnetism remaining in the coil. A normal-injection portion controls the fuel injector at full-open position.

Operating an engine system and fuel system includes energizing a solenoid actuator for a spill valve in a fuel injector in a first engine cycle via a standard waveform to inject a shot of fuel. Operating an engine system and fuel system further includes determining suitability for reduced energy operating of the fuel system, and energizing the solenoid actuator via a reduced energy waveform based on the determining suitability so as to inject one or more shots of fuel in a second engine cycle. The operating methodology and control logic can extend an engine speed range for multi-shot fuel injection in an engine.

A system for controlling the operation of one or more fuel injectors includes a microcontroller, a pre-driver unit, and a power unit. The system is connectable to an electrically actuated fuel injector via at least two wires from the power unit, wherein the pre-driver unit is located between the microcontroller and the power stage, and wherein the microcontroller unit is adapted to send data to the pre-driver unit. The pre-driver unit is adapted to receive the data and control the power stage dependent on the data such that the power stage is adapted to output a corresponding signal along the wires to the fuel injector. The data includes both injector activation pulse data and other auxiliary data for the injectors.

Methods and systems are provided for detection of a closing time for a solenoid valve. In one example, a method may include monitoring a current of the solenoid valve, filtering the current, and determining the closing time of the solenoid valve based on each of the current and the filtered current. In some examples, the solenoid valve may be an electrically-actuated fuel injection valve. In some examples, determining the closing time may include using the filtered current to determine an inflection point of the current.

An injection control device for a fuel injection valve includes: a current detection unit, a current area correction control unit, a storage unit, and a reference current value correction unit. The current area correction control unit corrects, based on an energization current profile, an area correction amount of an energization time to equalize the integrated current value of the energization current profile and an integrated current value of the detected current, and obtains the integrated current value of the current based on an attainment time from a start of energization of the fuel injection valve to an attainment of each of plural reference current values. The storage unit stores a reference attainment time. The reference current value correction unit corrects each reference current value based on a difference between the reference attainment time and a detected attainment time at a time of actual drive.

Various methods and systems are provided diagnosing a valve. In one example, a system comprises a valve configured to regulate a fuel flow, and a controller configured to determine degradation of the valve based on an initial opening characteristic of the valve.

A method for checking a parameter correlating with a pressure in a pressure-dependent fluid delivery system, the fluid delivery system having: a current-controlled electric motor controlled by a motor controller, and a fluid pump driven by the electric motor, includes: determining a rotational speed of the electric motor; determining a current of the electric motor, by reading out an activation current of the motor controller; calculating a pressure value as a function of the rotational speed and the current of the electric motor; and comparing the calculated pressure value with the parameter.

Methods and systems are provided for injecting fuel through three different rows of injector nozzles, where each row of the injector nozzle is arranged along a different vertical plane of the injector body. In one example, an injector needle housed movably inside the injector body may supply high-pressure fuel to each of the rows of injector nozzles sequentially to deliver up to five fuel injections in one actuation cycle of the fuel injector. In another example, a fuel injector may include three injector needles, where movement of each injector needle inside a respective chamber of the fuel injector body may supply high-pressure fuel to the chamber from where the fuel may be injected through the coupled fuel injector nozzles.

A method for switching over a solenoid valve having a movable valve body between a first position and a second position, wherein the method comprises at least the following method steps: a) adjusting a switching current to a pre-energization current intensity, in which the valve body remains in the present position, for a first time interval, and b) adjusting the switching current to a first switchover current intensity, which introduces a switchover movement of the valve body, for a second time interval.

A method for operating a speed-controlled fluid pump includes: providing an electrical control current for the fluid pump; providing a maximum value for the electrical control current, which maximum value corresponds to a maximum permissible pressure at an outlet side of the fluid pump; providing a threshold value for the control current, the threshold value corresponding to a further maximum permissible pressure at the outlet side of the fluid pump and is predefined in dependence upon at least one boundary condition, the threshold value being less than the maximum value for the electrical control current; and controlling the fluid pump with not more than the threshold value for the control current, if it has been determined that the at least one boundary condition holds, so as to limit the pressure at the outlet side of the fluid pump to a value provided for the at least one boundary condition.