Methods and systems are provided for injector balancing without disabling a cam actuated high pressure fuel pump. In one example, one of a plurality of cam lobes of the pump is selectively and sequentially disabled while a group of injectors are concurrently operated to learn a pressure drop across each injector. The selection of the injectors is based on the identity and stroke timing of the disabled cam lobe.

A direct-injection, supercharged internal combustion engine having at least one cylinder, in which each cylinder is equipped with a direct injection apparatus, a fuel supply system comprising a high-pressure side and a low-pressure side, and a high-pressure piston pump comprising a piston displaceable in translational fashion between a bottom dead center and a top dead center of a pressure chamber of variable volume. The displaceable piston jointly delimits the pressure chamber with variable volume in such a way that a displacement of the piston causes a change in the volume of the pressure chamber via actuation of least one movable actuation element.

Disclosed is a method for determining the configuration of a combustion engine of a motor vehicle including a step of detecting the reference position of the crankshaft, a step of controlling the control valve of the injection pump, after a predetermined time interval, a step of measuring a fuel pressure value in the injection rail, and a step of determining a first configuration of the engine when the fuel pressure value measured in the injection rail is greater than or equal to a first predetermined pressure threshold or determining a second configuration of the engine when the fuel pressure value measured in the injection rail is between a second predetermined pressure threshold and a third predetermined pressure threshold.

A method for operating an internal combustion engine having an injection system having a high-pressure accumulator, wherein an instantaneous high pressure in the high-pressure accumulator is monitored in a time-dependent manner by a high-pressure sensor. A first alarm stage is set, if a) a first predetermined high-pressure limit value is exceeded without interruption by the instantaneous high pressure for a predetermined limit time period, and/or b) if the first predetermined high pressure limit value is exceeded for the first time at a predetermined, first limit frequency by the instantaneous high pressure.

A lubricity estimation device is applied to a fuel supply system that supplies a fuel to an internal combustion engine, and includes a mixing ratio estimation unit and a lubrication index calculation unit. The mixing ratio estimation unit estimates the mixing ratio of each of plural types of molecular structures included in the fuel. The lubrication index calculation unit calculates a lubrication index, representing the lubricity of an outer peripheral portion S1 of the piston of a fuel pump and an outer peripheral portion of the valve body of a fuel injection valve by the fuel, based on the mixing ratio estimated by the mixing ratio estimation unit.

A controller of an internal combustion engine includes processing circuitry configured to execute a peak current command value calculating process of calculating a peak current command value, which is a command value of a peak current flowing through a coil, based on a detection value of a pressure in a delivery pipe, and a peak control process of controlling a value of the peak current at the peak current command value. The in-cylinder injection valve is configured to execute multi-stage injection including a first injection and a second injection carried out at a timing toward a retarding side from the first injection. A peak current command value for the second injection is larger than the peak current command value for the first injection.

Methods and systems are provided for calibrating engine port injectors. After pressurizing a low pressure fuel rail, a lift pump may be disabled and port injector variability may be correlated with a measured fuel rail pressure drop at each port injection event by sweeping injection pressure while maintaining injection voltage, and then sweeping injection voltage while maintaining injection pressure. A port injector variability map learned as a function of injection voltage and injection pressure is then transformed into a map learned as a function of injection current and injection pressure by accounting for injector variability caused due to changes in injector temperature.

A control device for a motor-driven fuel pump adapted for an internal combustion engine is provided. The fuel pump includes a cylinder, a mover in the cylinder, and an electric actuator configured to move the mover. The control device is configured to perform energization control on the electric actuator to reciprocate the mover so that the fuel pump draws in and discharges fuel. The control device is also configured to control a discharge count and a unit discharge amount based on an operating state of the internal combustion engine. The discharge count is a number of times of discharging fuel from the fuel pump to the fuel pipe during a period between a fuel injection from the fuel injection valve and the next fuel injection, and the unit discharge amount is an amount of fuel for one fuel discharge from the fuel pump.

Various embodiments include a method for adjusting an initial attenuation current for an injection valve comprising: moving a piston to a TDC; while moving the piston, closing an inlet valve; expelling the fluid; moving the piston away from TDC and applying an attenuation current to an electromagnet with the inlet valve still closed; switching a source for the attenuation current off; detecting an induction pulse resulting from an opening movement of the inlet valve by monitoring a current intensity signal of a subsequent decay in the current; adjusting a current intensity over a plurality of pump cycles to a current intensity level; checking for each current intensity level whether a time profile of the induction pulse satisfies a predetermined detention criterion; and when the detention criterion is satisfied, adjusting the current intensity level for future pump cycles to a lower current intensity level than the most recent level.

A fuel system for an internal combustion engine is provided including a first fuel container for a first fuel, a second fuel container for a second fuel, a pump, and a first fuel injector, the fuel system being arranged to provide a communication between the first fuel container and the pump and between the pump and the first fuel injector, and a reservoir with a separation device adapted to divide the reservoir into a first volume and a second volume, whereby the separation device may be moved or flexed by a pressure difference in the first and second volumes so as to change the sizes of the first and second volumes, wherein the fuel system is arranged to provide a communication between the pump and the first volume, and to provide a communication between the second fuel container and the second volume and between the second volume and a second fuel injector.