A control device includes a drive unit configured to supply electric power to a fuel injection valve to perform valve open drive to supply fuel to a combustion chamber of an internal combustion engine; and a correction unit configured to correct a fuel injection amount of the fuel injection valve. The correction unit is configured to learn the fuel injection amount of the fuel injection valve when NOx purge is performed to reduce and purify the NOx occlusion catalyst.

An internal combustion engine is provided. The internal combustion engine includes a control device, and at least one injector for liquid fuel. The injector(s) can be controlled by the control device via an actuator control signal. The injector(s) include an injector outlet opening for the liquid fuel which can be closed by a needle. A sensor is also provided for measuring a measurement variable of the injector(s). The sensor is or can be in a signal connection with the control device. An algorithm is stored in the control device, which algorithm calculates a state of the injector(s) based on input variables and an injector model, compares the state calculated via the injector model with a target state, and produces a state signal in accordance therewith. The state signal is characteristic of a change in the state of the injector(s) that occurs during intended use of the injector(s) and/or an unforeseen change in the state of the injector(s). The input variables include at least the actuator control signal and the measurement values of the sensor. A method for operating such an internal combustion engine and an injector is also provided.

Various embodiments include a method for operating a fuel injector comprising: applying a first current to a solenoid to perform a first injection process and inject a predefined injection quantity; determining a value of a system parameter indicating the relationship between the actual fuel quantity and the predefined quantity; determining, on the basis of the value of the system parameter, whether the actually injected fuel quantity is smaller than the predefined fuel quantity by a predefined amount corresponding to a disparity between a magnetic force exerted on the armature in the direction of the pole piece and an opposite hydraulic force exerted on the armature by fuel; and if it was determined that the quantities differ by enough, applying a second current to the solenoid to perform a second injection; wherein the second current exerts a lower magnetic force on the armature in the direction of the pole piece.

A prescribed air-fuel ratio feedback control region for performing feedback-control of air-fuel ratio has therein: a first region where fuel is injected, during one combustion cycle, only from a first fuel injection valve injecting fuel directly into a cylinder; and a second region where fuel is injected, during one combustion cycle, from both of the first fuel injection valve and a second fuel injection valve injecting fuel into an air-intake passage. A second region is configured such that an amount of fuel injected from the first fuel injection valve and an amount of fuel injected from the second fuel injection valve remain at a given constant ratio regardless of operating status. A diagnosis on the first and second fuel injection valves is performed by using a first air-fuel ratio learning value learned in the first region and a second air-fuel ratio learning value learned in the second region.

Provided is a technique for identifying a variation in an injection amount by estimating a valve opening start timing in an extremely small injection region of a half lift region. Therefore, a fuel injection control device according to the present invention estimates a valve opening start timing of a fuel injection valve by referring to a characteristic of a reference fuel injection valve acquired in advance.

A method of controlling an engine system includes controlling a fuel injector to perform a zero-fueling injector operation during operation of the engine, the zero-fueling injector operation including a non-zero injector on-time resulting in zero fueling by the injector, determining an injection system pressure change associated with the zero-fueling injector operation, modifying at least one fuel injection control parameter in response to the injection system pressure change, and using the modified fuel injection control parameter to control injection of fuel by the fuel injector during operation of the engine.

Various embodiments may include a method for actuating a fuel injector with a solenoid drive and a nozzle needle. The solenoid drive has a solenoid and a movable armature. The fuel injector has an idle stroke between the armature and the nozzle needle. An example method includes: applying a precharging current to the solenoid drive during a precharging phase to move the movable armature into mechanical contact with the nozzle needle; and applying a voltage pulse to the solenoid drive during a boost phase until the current intensity of the current flowing through the solenoid reaches a predetermined peak value.

A method for operating a fuel injection system for a vehicle is provided. In particular, the fuel injection system includes an injection nozzle having a nozzle body, a nozzle orifice and a nozzle needle movable in the nozzle body. The method including: measuring an actual injection timing of the injection nozzle during injection based on an electrical signal generated by the nozzle needle through an electric contact with the nozzle body so that the electrical signal identifies an open state and a closed state of the injection nozzle; calculating a deviation of the actual injection timing from a scheduled injection timing of the fuel injection system; and controlling the injection nozzle by adjusting injection parameters of the injection nozzle based on the evaluated deviation.

A method for identifying faulty components of a fuel injection system is disclosed, wherein a secondary injection is performed individually by each injector during a test routine, after the secondary injection several predefined parameters of the fuel injection system are determined, and a combined assessment of the determined parameters is used to draw conclusions about whether or not components of the fuel injection system are faulty.

Example embodiments relate to a method and a control unit, wherein a drive system having an electric machine and having an internal combustion engine with at least a first cylinder and a crankshaft is provided. A fuel feed to at least the first cylinder of the internal combustion engine is deactivated, wherein the electric machine is coupled fixedly in terms of torque to the internal combustion engine. The electric machine is actuated such that the crankshaft of the internal combustion engine rotates at a predefined rotational speed, wherein a first cylinder segment time duration, which is assigned to the first cylinder, is detected. A corrective value is determined in a manner dependent on the first cylinder segment time duration.