Systems and methods for diagnosing and operating an engine with a fuel pump that supplies fuel to a fuel injector that may be temporarily deactivated are described. In one example, injection of fuel may commence in response to a level of lubrication of a fuel pump. The system and methods may extend fuel pump life in systems where fuel injection may be deactivated.

An example system includes a controller configured to: receive pressure information indicative of a pressure level of the pressurized fuel between an electro-mechanical valve and an engine; based on the pressure level being below a first threshold pressure, send a first signal to open the electro-mechanical valve; determine, based on the pressure information, that the pressure level is increasing upon sending the first signal; in response to the pressure level increasing, send a second signal to activate a pump; determine that the pressure level has increased to a second threshold pressure; and provide information indicating that the engine is ready for operation.

A control device for a fuel injection system includes a CPU which generates a drive signal for instructing execution of compression by a fuel pump; a fuel pump drive circuit which controls application of electric power to a solenoid of the fuel pump based on the drive signal; a boost circuit provided with a capacitor for storing electric power to be used for driving an injector; a charging circuit which leads a current generated when the application of electric power to the solenoid is stopped to the capacitor; and an excess electric power consumption circuit which consumes excess electric power of the capacitor. While fuel injection from the injector is stopped, the CPU counts the number of times the fuel pump is driven and turns off the drive signal so as to stop driving the fuel pump as soon as the drive count has exceeded a predetermined count value.

The application is directed to a diesel engine. If the rack cannot complete a predetermined operation within a predetermined amount of time due to the key switch being held at a start-position, the control unit controls a starter to cause a plunger to perform a preparatory stroke operation, and the stroke operation by the plunger is stopped before the diesel engine starts.

Methods and systems are provided for performing mitigating actions in response to detecting a fuel injector leak. In one example, a method may include in response to detecting a fuel injector leak, performing first high pressure mitigating actions including increasing a fuel rail pressure, increasing a pulse width delivered to the leaking fuel injector, and commanding fuel injection during compression stroke; in response to the first mitigating actions not reducing the leak below a threshold rate, performing second high pressure mitigating actions including increasing the fuel rail pressure, increasing the pulse width delivered to the leaking injector, and commanding fuel injection during intake stroke for a cylinder receiving fuel from the leaking injector; and in response to the second mitigating actions not reducing the leak below the threshold rate, reducing the fuel rail pressure, and commanding intake stroke fuel injection to all cylinders.

Methods and systems are provided for performing mitigating actions in response to detecting a fuel injector leak. In one example, a method may include in response to detecting a fuel injector leak, performing first high pressure mitigating actions including increasing a fuel rail pressure, increasing a pulse width delivered to the leaking fuel injector, and commanding fuel injection during compression stroke; in response to the first mitigating actions not reducing the leak below a threshold rate, performing second high pressure mitigating actions including increasing the fuel rail pressure, increasing the pulse width delivered to the leaking injector, and commanding fuel injection during intake stroke for a cylinder receiving fuel from the leaking injector; and in response to the second mitigating actions not reducing the leak below the threshold rate, reducing the fuel rail pressure, and commanding intake stroke fuel injection to all cylinders.

During an operation, a control device (38) for performing output control of an engine (10) determines whether or not the engine (10) and/or an exhaust gas purifying device (18) has a malfunction. If it is determined that the engine (10) and/or the exhaust gas purifying device (18) has a malfunction, a highest rotational speed of the engine (10) is controlled to a second rotational speed (Nt) higher by a predetermined amount () than a first rotational speed (Ns) at which an engine maximum torque (Tm) before the malfunction can be outputted. In this case, a maximum fuel injection quantity of the engine (10) is limited so that a rated torque (Tr) before the malfunction can be outputted at the first rotational speed (Ns).

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 motor control device includes: a rotation control determination unit configured to determine whether a motor rotation control to rotate the motor fails; a parameter calculation unit configured to calculate a control failure frequency parameter having a correlation with a frequency of failure in the motor rotation control based on a determination result by the rotation control determination unit; an abnormality determination unit configured to determine whether an abnormality has occurred in the motor based on the control failure frequency parameter; and a stop suppression unit configured to suppress stop of rotation of the motor by changing a motor control parameter to perform the motor rotation control when the abnormality determination unit determines that an abnormality has occurred in the motor.

A system for determining fuel delivery includes an internal combustion engine having a plurality of cylinders, a plurality of fuel injectors configured to inject fuel for combustion in the cylinders, a fuel rail configured to provide the fuel to the plurality of fuel injectors, and a fuel pump configured to pressurize the fuel provided to the fuel rail. The system also includes a pressure sensor configured to detect a pressure of the fuel within the fuel rail and a controller configured to receive a pressure signal that indicates the pressure of the fuel detected with the pressure sensor, the pressure signal including pressure fluctuations caused by the fuel pump, and determine a quantity of the fuel injected by one or more fuel injectors of the plurality of fuel injectors, wherein the determination includes removing or reducing at least some of the pressure fluctuations caused by the fuel pump.