A fuel system includes a low-pressure fuel delivery unit and a high-pressure fuel delivery unit which has a low-pressure region and a high-pressure region such that the low-pressure region supplies fuel to the high-pressure region which supplies the fuel to a plurality of high-pressure fuel injectors. A low-pressure fuel rail supplies fuel to low-pressure fuel injectors. A low-pressure fuel injector line is connected at a first end directly to the high-pressure fuel delivery unit and receives fuel from the low-pressure region and is connected at a second end directly to the low-pressure fuel rail, thereby providing fluid communication from the low-pressure region to the low-pressure fuel rail. A device is located between the low-pressure region and the low-pressure fuel rail and reduces fuel pressure pulsations.

A fuel system includes a low-pressure fuel delivery unit and a high-pressure fuel delivery unit which has a low-pressure region and a high-pressure region such that the low-pressure region supplies fuel to the high-pressure region which supplies the fuel to a plurality of high-pressure fuel injectors. A low-pressure fuel rail supplies fuel to low-pressure fuel injectors. A low-pressure fuel injector line is connected at a first end directly to the high-pressure fuel delivery unit and receives fuel from the low-pressure region and is connected at a second end directly to the low-pressure fuel rail, thereby providing fluid communication from the low-pressure region to the low-pressure fuel rail. A device is located between the low-pressure region and the low-pressure fuel rail and reduces fuel pressure pulsations.

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.

A fuel pump includes a mechanical regulating valve arranged in a pump body which modulates the pressure in a high pressure space so that the pressure matches the engine demand. Modulation by the regulating valve requires adjustment of the inlet fuel quantity, adjustment of the volume of the high pressure space, and control of a return fluid communication enabling fuel to exit the high pressure reservoir.

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.

A fuel pump includes a mechanical regulating valve arranged in a pump body which modulates the pressure in a high pressure space so that the pressure matches the engine demand. Modulation by the regulating valve requires adjustment of the inlet fuel quantity, adjustment of the volume of the high pressure space, and control of a return fluid communication enabling fuel to exit the high pressure reservoir.

The invention relates to a fuel metering device for regulating the delivery rate of a high-pressure fuel pump of a fuel injection device for an internal combustion engine. The fuel metering device has a control valve actuated by an electromagnet and having a valve member. The electromagnet has an armature and an armature rod and the armature rod is axially movably supported in at least one bushing. The at least one bushing is designed as a solid, one-piece metal component. The bushing is preferably made of steel and the bearing surface thereof, in which the armature rod is supported, has a nitrocarburized and polished surface layer.

A system includes an actuation pump sub-system (APS) with an inlet configured to feed fuel from a fuel source into the actuation pump sub-system, a first outlet configured for connecting the APS in fluid communication with an afterburner selector valve, a second outlet, and a third outlet for connecting the APS in fluid communication with an actuation system to supply washed fuel flow for actuation. A main pump and control sub-system (MPCS) has a main inlet connected in fluid communication with the supply line downstream of the second outlet of the APS, and a main outlet for supplying fuel to a downstream gas generator. An afterburner pump in fluid communication to supply an afterburner control. An afterburner selector valve (ASV) in fluid communication with the MPCS, the wash line, and the afterburner pump.