A method for operating an engine in which fuel is supplied to the engine by a fuel pump and by a high-pressure fuel pump, and in which the speed of the fuel pump and/or the electrical current for feeding the fuel pump is controlled in accordance with a requirement variable, taking into account a determination specification. When the engine has changed to an overrun mode of operation, a calibration is performed and the speed of the fuel pump is detected and is maintained. Once the triggering pressure for a calibration valve has been reached, the pump current is detected, a bypass volumetric flow rate of the high-pressure fuel pump is determined during calibration using operating parameters and the triggering pressure for the calibration valve, the determined speed, the bypass volumetric flow rate and the determined pump current are used to calibrate the determination specification.

Disclosed is a method for estimating an angular position of top dead center for a high-pressure fuel injection pump that forms part of a system for injecting fuel into a motor vehicle engine, the pump including at least one piston moving in a chamber between the top and the bottom dead center, the pump being equipped with a digital control valve for controlling a quantity of fuel, an electrical current being applied to the digital valve as it closes then removed in order to open the digital valve, a movement of the digital valve in the direction of opening creating an induced current which makes it possible to detect a position of start-of-opening of the digital valve. An instant at which the pump piston passes through top dead center is estimated as a function of an instant at which the position of start-of-opening of the digital valve appears.

Disclosed is a method for detecting the direction of rotation of a crankshaft of an engine of a motor vehicle. The detection method includes in particular, when the crankshaft is in a second predetermined angular position between a low angular position and a high angular position of the crankshaft, a step of commanding the closure of a control valve for the intake of fuel into the high-pressure pump, a step of measuring a second pressure value in the high-pressure rail, and a step of detecting a nominal direction of rotation of the crankshaft if the second pressure value measured is greater than or equal to an expected pressure value or of detecting a reverse direction of rotation of the crankshaft if the second pressure value measured is less than the expected pressure value.

A control system includes a controller. The controller estimates the swing-back amount indicating the turning amount of the crankshaft in the reverse rotation direction until the crankshaft stops. The controller calculates a stop-time counter value which is a value of a crank counter at the time when the engine is stopped based on a final counter value which is the value of the crank counter calculated last before the crankshaft stops and the estimated swing-back amount. The controller corrects the swing-back amount used for calculating the stop-time counter value based on a difference between the number of driving times calculated with reference to the map based on the calculated stop-time counter value and the value of the crank counter and the number of driving times calculated by increasing the number of driving times by one each time the high pressure system fuel pressure increases by the threshold or more.

A control system includes a controller. The controller counts the number of driving times of the high pressure fuel pump, which is the number of the reciprocating motions of the plunger based on a crank counter that is counted up at every predetermined crank angle. The controller stores a map in which a top dead center of the plunger is associated with a crank counter value, and store a crank counter value while an engine is stopped as a stop-time counter value. The controller calculates, referring to the map, the number of the crank counter values corresponding to the top dead center of the plunger between a crank counter value and the stop-time counter value, and set a calculated number as the number of driving times.

A control system includes a controller. The controller counts the number of driving times of a high pressure fuel pump, which is the number of reciprocating motions of a plunger based on a crank counter. The controller estimates a high pressure system fuel pressure based on the calculated number of driving times, a fuel temperature detected by a fuel temperature sensor, and a low pressure system fuel pressure detected by a low pressure system fuel pressure sensor when the high pressure system fuel pressure is not able to be acquired from a high pressure system fuel pressure sensor. The controller sets an opening period of an in-cylinder fuel injection valve based on the estimated high pressure system fuel pressure and to perform an engine start by an in-cylinder fuel injection when the high pressure system fuel pressure is not able to be acquired from the high pressure system fuel pressure sensor.

To reduce collision noise caused when an electromagnetic valve of a high-pressure fuel supply pump is opened. Therefore, in a control device for controlling a high-pressure fuel supply pump including: an anchor; a fixed core configured to attract the anchor with an electromagnetic force; a suction valve configured to be opened or closed when the anchor is sucked by the fixed core; and an electromagnetic force generation unit configured to generate the electromagnetic force when applied with a driving voltage, it can be achieved by providing a control unit configured to perform control to lower a driving current from a peak current before a timing at which the anchor is sucked by the fixed core and collides in an operation state where an engine is under no load and an engine rotation speed is equal to or less than a set rotation speed.

A method of testing a fuel injection system or components thereof includes running a high pressure fuel pump to provide fluid under pressure to the fuel injection system or components. The pump flow is controlled via an inlet metering valve by controlling current or voltage supplied to the inlet metering valve dependent on the power to the fuel pump.

A method for operating an internal combustion engine having an injection system which has a high-pressure accumulator, wherein a high pressure in the high-pressure accumulator is regulated via a suction throttle on the low-pressure side as a first pressure control member in a first high-pressure control loop, wherein in a normal operation a high-pressure disturbance variable is produced via a pressure control valve on the high-pressure side as a second pressure control member, via which fuel is redirected from the high-pressure accumulator to a fuel reservoir. For this purpose, the high pressure in a safety operation is regulated by the pressure control valve via a second high-pressure control loop, or, in the safety operation, a maximum fuel volume flow is continuously redirected from the high-pressure accumulator to the fuel reservoir via the pressure control valve.

A fuel pump includes a cylinder that forms a compression chamber which pressurizes a fuel, a plunger that compresses the fuel in the compression chamber, a cam that pushes the plunger, and a driven gear that engages a driving gear to transmit a rotational driving force. A profile of the cam is configured such that a peak arrival range is half or less of a compression range. Cam speed is obtained by differentiating a lift amount of the plunger by a rotation angle of the cam, the compression range is an angle range during which the plunger is pushed in the direction of compressing the fuel, and the peak arrival range is an angle range from a start of the compression range until a most retarded position of a peak of the cam speed.