A method of preventing an engine stall of a vehicle having a fuel injection device for pressurizing fuel stored in a fuel tank by a high-pressure fuel pump to transmit the fuel to a common rail, and injecting the fuel temporarily stored in the common rail into an engine through an injector may include steps of determining whether or not a drift occurs in an output signal of a high-pressure fuel pressure sensor for measuring fuel pressure at a downstream side of the high-pressure fuel pump, and performing a fuel pressure control by replacing a high-pressure fuel pressure value with a predetermined pressure value based on the output signal of the high-pressure fuel pressure sensor.

Methods and systems are provided for calculating a fuel aging of fuel in a fuel tank. In one example, a method may include alerting a vehicle operator and/or adjusting engine operating parameters in response to a fuel aging being greater than a threshold aging.

A method for regulating a fuel delivery system without a pressure sensor. The fuel delivery system has a fuel delivery pump, an electric motor, and an evaluation unit. The fuel delivery pump is driven by the electric motor, which is actuated using control variables such that a prespecifiable fuel delivery is achieved. At least two different submethods are executed for ascertaining control variables, which are ascertained in the respective submethod and are supplied to an evaluation unit. The control variables are evaluated regarding their plausibility in the evaluation unit and the electric motor is actuated based on the ascertained control variables from only one or a plurality of submethods.

Methods and systems are provided for controlling a fuel system of a vehicle to diagnose whether a fuel filter is functioning as desired. In one example, a method may include, in response to a fuel rail pressure decreasing below a threshold pressure while an engine of the vehicle is running, diagnosing whether degradation of fuel injectors or a fuel pressure regulator of the vehicle has occurred while the engine is not running. Then, only if degradation of the fuel injectors and fuel pressure regulator has not occurred, a fuel filter cleaning routine is performed.

An engine control device controls an engine including a turbo-supercharger, a waste gate valve, an air-bypass valve, and a high-pressure fuel system. The engine control device includes: an air-bypass valve control unit and an abnormality detection unit. The air-bypass valve control unit controls the air-bypass valve. The abnormality detection unit detects an abnormality in the high-pressure fuel system. The air-bypass valve control unit increases an opening degree of the air-bypass valve in accordance with detection of the abnormality by the abnormality detection unit.

Methods and systems for evaluating whether or not a fuel amount that is greater than a threshold has been release to an engine via fuel injectors when the fuel injectors are commanded off are presented. In one example, an oxygen sensor is activated and engine cranking is prevented until a pumping current of the oxygen sensor is proportionate to a concentration of oxygen sensed via the oxygen sensor so that released fuel may be observed during engine starting.

The invention relates to a method for testing an electrically activated actuator in a fuel delivery device (10) of an internal combustion engine, wherein the electrical actuator is a controllable valve (15) that is arranged on the inlet side of a high-pressure pump (16). The high-pressure pump (16) conveys fuel into a fuel store (17) having a pressure controller (20). The fuel store (17) is connected to at least one injector (23). The method comprises the following steps: 1) increasing the rotational speed of the high-pressure pump (16), 2) activating the controllable valve (15) until the pressure in the fuel store (17) has reached a first low pressure level, 3) changing the supply of current to the controllable valve (15) by a first specified value such that the controllable valve (15) is opened further and simultaneously maximizing an injection amount by means of the at least one injector (23) until the pressure in the fuel store (17) has reached a first threshold value, 4) activating the controllable valve (15) until the pressure in the fuel store (17) has reached the first low pressure level again, 5) determining a further quantity, which depends on the low pressure level and a maximum value of the pressure that was reached in the fuel store (17).

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.

Methods and systems are provided for calibrating engine port injectors. After pressurizing a low pressure fuel rail, a lift pump may be disabled and port injector variability may be correlated with a measured fuel rail pressure drop at each port injection event by sweeping injection pressure while maintaining injection voltage, and then sweeping injection voltage while maintaining injection pressure. A port injector variability map learned as a function of injection voltage and injection pressure is then transformed into a map learned as a function of injection current and injection pressure by accounting for injector variability caused due to changes in injector temperature.

A controller of an engine performs a failure diagnosis process for an injection valve. The failure diagnosis process increases a misfire count of the engine when a variation in rotation of the engine is equal to or greater than a predetermined variation in every predetermined cycle, and determines that the injection valve has a failure when the misfire count is equal to or greater than a first predetermined number of times over a predetermined time period. The controller determines that the multi-cylinder engine is in a predetermined load operation cycle if a volume efficiency of the multi-cylinder engine is less than a reference value, and the controller determines whether continuation of the injection mode is needed based on a comparison of the misfire count and a second predetermined number of times, wherein the second predetermined number of times is less than the first predetermined number of times.