A fuel supply device includes an injector, a fuel pressurization device and an ECU. The fuel pressurization device includes an electromagnetic valve. The fuel pressurization device is configured to pressurize a fuel in accordance with opening/closing of the electromagnetic valve and discharge the fuel toward the injector. The ECU is configured: to control the opening/closing of the electromagnetic valve to adjust the fuel amount discharged toward the injector; to execute an operation sound suppression control during a low-load operation of an engine by reducing an opening/closing frequency of the electromagnetic valve and increasing the fuel amount discharged for each opening/closing of the electromagnetic valve; not to execute the operation sound suppression control when a partial lift injection is in progress; and to execute the operation sound suppression control when the partial lift injection is not in progress.

When a rotational speed of an engine is higher than a predetermined rotational speed, a low-pressure fuel injection valve is controlled through the use of a fuel injection time based on an estimated fuel pressure in a low pressure supply pipe and a target fuel injection amount. When the rotational speed of the engine is equal to or lower than the predetermined rotational speed, the low-pressure fuel injection valve is controlled through the use of a fuel injection time based on a detected fuel pressure input from the fuel pressure sensor from the issuance of a command to activate energization of a solenoid to the start of energization of the solenoid and a target fuel injection amount.

Systems and methods for improving fuel injection of an engine that includes a cylinder receiving fuel from two different fuel injectors is disclosed. In one example, fuel is supplied to port fuel injectors and direct fuel injectors via a same high pressure fuel pump, and high pressure port fuel injection is activated at times where direct fuel injection would supply less fuel than is desired or an inconsistent amount of fuel.

Methods and systems are provided for reducing hot fuel vapor formation in a port injection fuel rail. In one example, a method may include operating a dual fuel injection system with at least a calibrated minimum amount of port fuel injection over a wide range of engine operating conditions, even as conditions change. A direct fuel injection amount is adjusted in accordance.

Methods and systems are provided for controlling a low pressure pump in port fuel direct injection (PFDI) engines. One method includes, when operating a high pressure pump in a default pressure mode, pulsing the low pressure pump when pressure in a high pressure fuel rail decreases below a threshold. The method further includes, when operating the high pressure pump in a variable pressure mode, pulsing the low pressure pump based on presence of fuel vapor at an inlet of the high pressure pump.

Methods and systems are provided for delivering fuel to a port injector fuel rail in a port fuel direct injection (PFDI) engine. In one example, the port injector fuel rail may receive fuel from each of a compression chamber and a step chamber of a direct injection fuel pump coupled in the PFDI engine. In this way, pressurized fuel may be supplied to the port injector fuel rail during an entire cycle of the direct injection fuel pump.

A smoothing coefficient is set value such that a value of smoothing coefficient when the fuel pressure difference is larger than the threshold value is larger than a value of smoothing coefficient when a fuel pressure difference between a target fuel pressure and a detected fuel pressure is equal to or smaller than a threshold value. A smoothened fuel pressure is calculated by performing fuel pressure smoothing processing on the detected fuel pressure, using the smoothing coefficient. An in-cylinder injection valve is controlled such that fuel is injected during a target fuel injection duration according to the smoothened fuel pressure from the in-cylinder injection valve.

A storage device is configured to store a first mapping that receives, as an input, a first input variable including a cam phase variable on present and past phases of a cam, and output a pulsating variable on a pulsating component. The execution device is configured to acquire the first input variable and estimate the pulsating variable by applying the acquired first input variable to the first mapping. Therefore, it is possible to estimate the pulsating variable without providing a low-pressure fuel pressure sensor by estimating a fuel pressure variable by applying the first input variable to the first mapping.

A fuel pressure estimation system estimates a fuel pressure variable on a fuel pressure in a supply pipe for an engine apparatus including an engine having a fuel injection valve, and a fuel supply device having a fuel pump that supplies the fuel in a fuel tank to the supply pipe, and includes a storage device and an execution device. The storage device stores a first mapping that receives, as an input, first input variables including a pump variable, a consumption flow rate variable on a consumption flow rate of the fuel, and a property variable on a property of the fuel, and outputs the fuel pressure variable. The execution device acquires the first input variables and estimates the fuel pressure variable by applying the first input variables to the first mapping.

A control device is applied to a fuel supply system including a fuel pump that rotates an impeller in a housing and pumps fuel from a fuel tank and a fuel pipe in which fuel discharged from the fuel pump flows. The control device controls the fuel pump. The control device includes an execution device and a storage device that stores a program of a process which is performed by the execution device. In the control device, the execution device performs a coping process of increasing an amount of operation of the impeller when the impeller is deformed and interference with the housing is detected in comparison with a case in which the interference is not detected.