The present disclosure relates generally to a method for determining a failure of a flow divider within a fuel system, the method being performed by a controller and comprising the steps of: delivering a fuel command, calculating an expected fill time, wherein the expected fill time is indicative of the time required to fill a known fuel manifold volume, determining whether the actual fill time is greater than or equal to an expected fill time; and determining whether an actual fuel pressure value is less than or equal to an expect fuel pressure value based at least in part on at least one environmental signal.

A control device for an internal combustion engine includes a fuel tank, a high pressure fuel passage, a pressure increasing device, a switching device, a low pressure fuel passage, a temperature sensor, a fuel injector, and an electronic control unit. The electronic control unit is configured to determine that there is an abnormality in the switching device when a temperature measured by the temperature sensor when the pressure increase signal is output is not higher than a temperature measured by the temperature sensor when the pressure increase signal is not output. The electronic control unit is configured to stop fuel pressure increase by the pressure increasing device by stopping an output of the pressure increase signal regardless of the engine operation state when the electronic control unit determines that there is the abnormality in the switching device.

Provided is a method for diagnosing unintended fuelling from one or more fuel injectors of a multi cylinder internal combustion engine during engine operation. Pressurized fuel is intended to be distributed by means of said fuel injectors from said accumulator tank to the cylinders for combustion. An oxidation catalyst is arranged downstream said cylinders. The method comprises: determining the pressure in the fuel accumulator tank and whether said pressure is decreasing; and determining whether the actual amount of fuel provided by the pump unit exceeds the demanded amount of fuel. The method further comprises the steps of: determining whether the temperature associated with the oxidation catalyst is above a certain level and/or determining whether the air/fuel ratio is below a certain level and/or determining whether an amount of particulate matter is above a certain level; and confirming an unintended fuelling based on the determined conditions.

An alarm system is used for a vehicle including a fuel pump and an engine. The alarm system includes a measuring device, a computing device and a warning device. The measuring device is used to read a current rotation speed of the engine and respectively measures a plurality of running times of a plurality of rotation speed values of the current rotation speed. The computing device calculates a plurality of consuming times of the fuel pump corresponding to the rotation speed values according to the running times of the rotation speed values, respectively. When an accumulating consuming time accumulated by the consuming times reaches a default critical value, the warning device generates a warning message.

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.

Various methods and systems are provided for diagnosing a condition of a fuel injector of an engine. In one example, a method for an engine includes injecting a first pulse of fuel as a first pilot injection into a first subset of cylinders of a plurality of engine cylinders, where the first pilot injection precedes a primary injection of fuel into the first subset of cylinders by a duration; correlating a first response in an engine operating parameter to the first pilot injection; and adjusting the primary injection of fuel into the first subset of cylinders based on the first response. In one example, the first pilot injection precedes the primary injection by a predefined short duration and the primary injection of fuel is adjusted within a predefined or preset upper limit and lower limit.

An engine control apparatus includes first and second fuel injection amount calculators, a fuel injection controller, an EGR valve controller, and an EGR valve diagnosis unit. The first and second fuel injection amount calculators are configured to calculate first and second fuel injection amounts on the basis of a detected intake air amount and detected pressure in an intake pipe, respectively. The fuel injection controller is configured to control a fuel injection apparatus for an engine on the basis of a correction fuel injection amount that is a result of addition of the first and second fuel injection amounts respectively multiplied by first and second weight coefficients. When the fuel injection is restarted after diagnosis of the EGR valve carried out by the EGR valve diagnosis unit, the fuel injection controller increases the second weight coefficient, and thereafter gradually increases and reduces the first and second weight coefficients, respectively.

A circuit and a method for a digital inlet valve having a shutter moveable between a closed and an open position and actuated by a linear electromagnetic actuator including a movable needle located inside a coil winding connected to a power source by a first electronic switch. An electric current is supplied to the coil winding. A parameter indicative of a movement of the needle is monitored. The electric current supply is adjusted when the monitored parameter exceeds a predetermined value.

A vehicle includes an engine and a controller programmed to, responsive to an estimated oil dilution level of the engine exceeding a first threshold, issue commands such that regenerative braking is inhibited to increase a temperature of the engine, and responsive to the estimated oil dilution level falling below the first threshold, discontinue issuing the commands.

A method for operating a fluid delivery system of a vehicle powerplant is provided. The method includes sampling a fluid pressure in a port injection section of the fluid delivery system, determining if an isolation valve positioned upstream of a direct injection pump is degraded based on the fluid pressure, where the isolation valve separates the port injection section from a direct injection section, and when it is determined that the isolation valve is degraded, indicating said degradation of the isolation valve.