A fuel injection apparatus for an internal combustion engine includes a fuel supply line in communication with a fuel tank and a fuel pump system. A fuel rail is connected to the fuel supply system and a plurality of fuel injectors. A return line extending from the fuel rail to the fuel tank. A by-pass passage extending from the supply line to the return line and including a pressure release valve having a pre-set activation pressure. A fuel temperature sensor for sensing a feed temperature of the fuel in the fuel supply system. A pressure control module that sets a first pressure set point in the fuel rail below the pre-set activation pressure when the feed temperature is below a predetermined temperature and sets a second pressure set point above the pre-set activation pressure of the pressure release valve when the feed temperature is above the predetermined temperature.

A method for controlling a fuel pressure valve of a vehicle may include stop entrance, of reducing a target fuel pressure below a predetermined value based on an engine RPM and increasing an allowable deviation between the target fuel pressure and an actual fuel pressure measured by a sensor when a controller determines that a current vehicle speed is equal to or lower than a reference vehicle speed, and pressing of an acceleration pedal is released, fuel pressure determination, of determining whether a deviation value between the target fuel pressure and the measured actual fuel pressure is greater than the allowable deviation, and valve control, of determining a duty value of the fuel pressure valve when the deviation value between the target fuel pressure and the measured actual fuel pressure is greater than the allowable deviation, and then controlling to open the fuel pressure valve using the determined duty value.

A method and system for controlling a fuel pressure valve of a vehicle are disclosed. The disclosed control method includes engine start entrance for controlling a controller to increase an allowable deviation between a current target fuel pressure and an actual fuel pressure when an ignition switch-on signal is received by the controller, fuel pressure determination for controlling the controller to determine whether a deviation value between the target fuel pressure and an actual fuel pressure measured by a sensor is greater than an allowable deviation, and valve control for controlling the controller to determine a duty value for control of opening of the fuel pressure valve, and then controlling the controller to open the fuel pressure valve using the determined duty value, thereby decreasing the actual fuel pressure.

A fuel pump includes a camshaft that rotates in accordance with operation of an engine and a tappet provided in contact the camshaft. An ECU includes an angle determination unit configured to determine whether a rotation angle from a start of rotation of the camshaft when starting the engine is under a predetermined angle required for forming an oil film on a sliding portion of the tappet, and a control unit configured to, when the rotation angle from the start of rotation of the camshaft is determined to be under the predetermined angle, execute a limit process including at least one of limiting a fuel discharge pressure of the fuel pump or limiting a rotation of the camshaft.

A method may comprise: positioning a pressure control valve (PCV) at an outlet of a fuel rail; positioning a volume control valve (VCV) at an inlet of a high pressure pump; and in response to an exhaust particulate matter (PM) level deviating from a target PM level, adjusting a fuel ratio of a first fuel and a second fuel delivered to an engine, and opening one of the PCV and the VCV. In this way, the fuel oxygen content may be adjusted to maintain a PM at or below a target level without a DPF over a broad range of engine designs and operating conditions, while maintaining fuel economy.

An illustrative example method of controlling an engine of a vehicle, includes determining a target pressure curve for a cylinder of the engine, determining a heat release model for the cylinder, determining a mass flow of fuel from the heat release model to achieve the target pressure curve, and automatically controlling opening of an injector of the cylinder of the engine to provide the determined mass flow of fuel to the cylinder.

A common rail fuel injection device includes first and second flow rate regulating valves for regulating a delivery volume of a pressurized fuel feed pump that feeds pressurized fuel to a common rail, a pressure reducing valve for reducing a common rail pressure, and a control device. The control device for the common rail fuel injection device includes a first drive controlling unit that controls a first electromagnetic driving unit for the second flow rate regulating valve and a second electromagnetic driving unit for the pressure reducing valve, and a second drive controlling unit that controls a third electromagnetic driving unit for the first flow rate regulating valve. The first drive controlling unit prohibits a drive instruction from being sent to the second flow rate regulating valve when the first drive controlling unit sends a drive instruction to the pressure reducing valve.

Methods for controlling a Methods for controlling a valve disposed at an engine of a vehicle are disclosed. In one form of the disclosure, the method includes: determining whether an engine is an idle state; measuring a fuel pressure of the engine when the engine is the idle state; comparing the measured fuel pressure with a first threshold value; and operating the valve by applying a current to a valve operation coil when the measured fuel pressure is equal to or less than the first threshold value for a predetermined time or longer.

Methods and systems are provided for adjusting operation of fuel injectors of an internal combustion engine to reduce injector ticking noise during direct injection fuel rail pressure release. The method includes first reducing a significant part of the direct injection fuel rail pressure via a mechanical high pressure pump relief valve and only if further pressure relief is required then intermittently activating the direct injector to inject in small amount of fuel. Due to the reduced frequency of activation and small pulse-widths, the impact force transmitted from injectors to cylinder head is small thereby reducing the objectionable ticking noise.

The required fuel supply amount of an internal combustion engine is reduced by limiting the throttle opening when a high-pressure fuel pump is required to discharge fuel that exceeds the fuel delivery capacity thereof. Further, when the throttle opening is limited, the operation of a return valve, through which fuel and vapor thereof can be discharged from the high-pressure fuel pump, is prohibited. By performing the abovementioned control, a reduction in the fuel delivery amount of the high-pressure fuel pump due to the operation of the return valve is prevented when there is a possibility that the fuel deliver amount of the high-pressure fuel pump runs short and the fuel supply amount of the internal combustion engine runs short.