A system for detecting a pre-fill status of a fuel filter in a fuel system includes a monitoring mechanism structured to monitor a fluid property of the fuel system indicative of priming. A control mechanism is coupled with and structured to received data from the monitoring mechanism, and outputs a signal responsive to a time to prime the fuel system that is indicative of a filter pre-fill state.

A diagnosis device for an evaporated fuel processing device includes: a pump arranged to pressurize or depressurize a system including the fuel tank and the canister; at least one pressure sensor arranged to sense a pressure within the system; and a fuel temperature sensor arranged to sense a temperature of a fuel within the fuel tank, the diagnosis device being configured to select a first leakage diagnosis using a positive pressure or a negative pressure existing within the fuel tank, or a second leakage diagnosis using a forcible pressurization or a forcible depressurization by the pump, based on a temperature difference between a fuel temperature at a start of driving, and a fuel temperature after an end of the driving, with respect to a request of a leakage diagnosis.

An engine includes a plurality of combustion cylinders configured to burn a fuel to power the engine, and a plurality of fuel injectors. Each of the fuel injectors is arranged to distribute fuel delivered from a fuel tank to one of the plurality of combustion cylinders. The engine also includes a controller programmed to adjust a fuel trim signal gain based on sensing exhaust flow downstream of the combustion cylinders. The controller is also programmed to monitor a cumulative misfire count for each of the plurality of combustion cylinders. The controller is further programmed to issue a prognosis message identifying a state of health of at least one of the plurality of fuel injectors in response to a fuel trim signal gain exceeding an adjustment threshold and a cumulative misfire count greater than a misfire threshold.

A method for detecting a sticking tank vent valve in a motor vehicle, a temperature sensor being situated in a tank vent line between the tank vent valve and an inlet point into an intake manifold or into a turbocharger and sticking of the tank vent valve being detected when the absolute value of a correlation of a calculated tank ventilation mass flow and of a signal value of the temperature sensor violates a predefinable threshold value.

An engine fuel delivery system includes a fuel pump having a pumping chamber to increase fuel pressure and a closeable inlet valve, and a fuel rail to communicate pressurized fuel received from the fuel pump to at least one engine cylinder. The engine fuel delivery system also includes a controller programmed to issue a control signal to periodically close the inlet valve to generate a setpoint fuel pressure within the pumping chamber. The controller is also programmed to adjust a control signal gain value in response to deviation in an outlet fuel pressure relative to the setpoint fuel pressure. The controller is further programmed to issue a warning message in response to the control signal gain being adjusted by more than a predetermined threshold from a calibrated gain value.

A booster pump increases fuel pressure in a high-pressure system of a fuel supply system. A decompression mechanism reduces the fuel pressure. In case of a discharge abnormality of the booster pump which causes rise in the fuel pressure, the fuel pressure control system performs an abnormality handling to cause the decompression mechanism to stop the rise in the fuel pressure. In case of the discharge abnormality, and on determination of a warning-required state, in which the fuel pressure in the high-pressure system possibly exceeds a threshold pressure, a control device causes a warning state, in which the fuel pressure does not exceed the threshold pressure before the rise in the fuel pressure stops, even if the discharge abnormality occurs.

After a system-off state has continued for a preset, time period since a system-off operation, on satisfaction of abnormality diagnosis prerequisites including a condition that a warm-up determination parameter indicating a degree of warm-up of an engine at a system-off time is equal to or greater than a predetermined value, characteristic abnormality diagnosis is performed to determine whether a characteristic abnormality occurs in a fuel pressure sensor. For a time period from a system-on operation to a system-off operation, the warm-up determination parameter is incremented when the engine is in operation, while being decremented after satisfaction of a predetermined condition when the engine is not in operation.

A method for operating an engine system 200 comprising an engine 208 configured to consume a fuel, having at least a two flowmeters 214, 216, is provided. The method includes the step of operating an engine 208 disposed between a supply flowmeter 214 of the at least two flowmeters and a return flowmeter 216 of the at least two flowmeters. A first fuel density in the supply flowmeter 214 and a second fuel density in the return flowmeter 216 are measured. The fuel density measurements 317 between the supply flowmeter 214 and return flowmeter 216 are compared and a differential density measurement value, ?? 319, based on a difference in the second fuel density and the first fuel density is determined. The ?? 319 is compared to a range of theoretical differential fuel density values, ??.sub.t, and potential fuel contamination is indicated if the ?? lies outside a range of ??.sub.t values by a predetermined threshold.

A method is described to control an actuation profile of an electromechanical linear actuator device of an internal combustion engine designed to control the movement of a component; the internal combustion engine comprises a sensor, which faces the actuator device and is designed to detect the noise generated by the movement of the component; the method comprises the steps of acquiring, by means of the sensor, the intensity of a signal generated by the impact of the component against a limit stop; identifying a first listening window of the signal associated with said impact; calculating a noise index inside the listening window; comparing the noise index with a reference value; and controlling the actuation profile of the actuator device based on this comparison.

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.