Abstract: Engine cylinder reactivation from a fuel-cut state is controlled based on a calculated future engine speed and a minimum allowable engine speed. The future engine speed is calculated based on the current rate of change of engine speed and a duration required to reactivate an engine cylinder. The duration can be in the time domain, or engine event domain, for example.

Abstract: A leisure vehicle comprising an electronic control throttle system of an engine in which an actuator drives a throttle valve in response to an operation signal according to an operation amount of a throttle operation device, the electronic control throttle system including a throttle valve controller configured to send a control signal to the actuator to drive the throttle valve. The throttle valve controller is configured to give a gain to compensate for a deviation between a target opening degree of the throttle valve that is set based on the operation amount of the throttle operation device and an actual opening degree of the throttle valve which is a detected opening degree of the throttle valve. The throttle valve controller is configured to set the gain that causes the throttle valve to enter an overshooting region that exceeds a fully open position in a movement range of the throttle valve.

Abstract: A requested injection amount of fuel necessary during ignition cut-off at the time of start at an extremely low temperature is calculated (step ST2), injection start timing and injection end timing between which wetting of a spark plug by fuel is less likely are set (step ST3), and the number of times of ignition cut-off is calculated based on the injection start timing and the injection end timing and the requested injection amount (step ST4). The injection start timing and the injection end timing are thus restricted to timings between which plug wetting is less likely, and the number of times of ignition cut-off is calculated based on the injection start timing and the injection end timing and the requested injection amount, so that wetting of the spark plug by fuel at the extremely low temperature can be avoided even in an in-cylinder direct-injection engine.

Abstract: A control system for an internal combustion engine having a fuel injection valve. A fuel injection timing is determined according to the detected engine operating condition. A target ignition timing of the fuel is calculated using a plurality of maps that store the target ignition timings according to the engine operating condition and an actual ignition timing of the fuel is detected. An ignition delay of the actual ignition timing with respect to the target ignition timing is calculated. The cetane number of the fuel is estimated according to the calculated ignition delay. The map to be used in calculating the target ignition timing is switched according to the estimated cetane number.

Abstract: In an engine of a working machine having no governor mechanism, the engine revolution speed is controlled such that the revolution speed can stably be maintained irrespective of the variation in load without adjusting the throttle opening to exploit the full potential of the engine. Since an engine 1 does not have the governor mechanism, an operator adjusts the throttle opening and controls the engine revolution speed. A map in which ignition timing (amount of angle of lead) is set by means of functions of the engine revolution speed is stored in an ignition timing map 30. The map 30 is set such that the engine revolution speed is equal to or higher than a value to be controlled (e.g. 7000 rpm), and the ignition timing is lagged as compared with a case in which the engine revolution speed is lower than the value to be controlled.

Abstract: An auxiliary device for sparkplug ignition is provided having a case, and provided therein, electrolytic capacitors connected in parallel between ground terminals and positive terminals of the primary coils of the ignition coils, which are connected to sparkplugs in a direct ignition system. Diodes, which are connected in parallel, are provided in the reverse direction, between the ground terminals and the positive terminals on the primary coils. The case is fitted with a connector that connects to a dedicated harness. The back electromotive force generated in the primary side coils L1 to L4 of the ignition coils of each sparkplug is absorbed, so as to adjust the primary side current, allowing for generation of stabilized high voltage on the secondary coil side, and producing highly efficient sparkplug ignition.

Abstract: For setting a predetermined target control amount concerning running of a vehicle according to an operation amount for a predetermined operation member for running the vehicle, an operation amount obtaining part obtaining the operation amount for the operation member; a trouble determining part determining whether or not a trouble occurs in any one of the operation member and the operation amount obtaining part; a target control amount setting part setting a trouble occasion target control amount which is a target control amount for a trouble occasion when the trouble determining part determines that a trouble occurs in at least any one of the operation member and the operation amount obtaining part; and a correcting part correcting the trouble occasion target control amount set by the trouble occasion target control amount setting part in such a manner that on-spring vibration of the vehicle is damped, are provided.

Abstract: An electronic throttle valve system more suitable for use in straddle type vehicles. A straddle type vehicle has an electronic throttle valve system for adjusting the amount of intake air to an internal combustion engine. The electronic throttle valve system includes a throttle valve, an electric motor and a control unit. A guard mechanism is provided on a valve shaft of the throttle valve. The guard mechanism includes a pulley with which the throttle cable is engaged and a lever pulley which rotates in conjunction with the opening of the pulley. A cushion spring is provided on an edge face of a notched portion of the lever pulley, the edge face generally coming into contact with a protrusion that extends from the valve shaft of the throttle valve.

Abstract: A system and method for utilizing a humidity sensor with an internal combustion engine of a vehicle is described. Specifically, information from the humidity sensor is used to adjust a desired air-fuel ratio to reduce engine misfire while improving vehicle fuel economy. Further, such information is also used to adjust timing and/or lift of the valve in the engine cylinder. Finally, diagnostic routines are also described.

Abstract: If a high-pressure pump discharges fuel in an injection waiting period from injection setting to injection start, fuel pressure to occur at injection start time is estimated and a fuel pressure correction coefficient is calculated based on the estimated fuel pressure. If there is no fuel discharge in the injection waiting period, the fuel pressure sensed at the injection setting is regarded as the fuel pressure of the injection start time, and the fuel pressure correction coefficient is calculated based on the sensed fuel pressure. A final injection period is calculated by correcting a basic injection period with the fuel pressure correction coefficient. Thus, fuel pressure correction of the injection period is performed accurately even if actual fuel pressure fluctuates due to the fuel discharge from the high-pressure pump during the injection waiting period.

Abstract: An ECU performs stop control for operating an engine for a prescribed time after an ignition switch is turned off. During performance of the stop control of the engine, the ECU prohibits an update of an accelerator press-down degree signal and controls an opening degree of a throttle valve such that, the opening degree of the throttle valve becomes constant regardless of an amount of pressing-down of an accelerator pedal, in order to prevent a variation in an output of the engine due to an operation of the accelerator pedal.

Abstract: A boost system for an engine, comprising an engine having at least a cylinder; a fuel injector coupled to said cylinder; a compression device coupled to said engine; a compressed air storage device coupled to said compression device and configured to deliver compressed air to an air flow amplifier device located in the inlet air passageway to said cylinder; and a controller to adjust an amount of fuel injection to account for variation of air delivered to said cylinder from said flow amplifier device.

Abstract: An electronic throttle valve system more suitable for use in straddle type vehicles. A straddle type vehicle has an electronic throttle valve system for adjusting the amount of intake air to an internal combustion engine. The electronic throttle valve system includes a throttle valve for adjusting the amount of intake air to the internal combustion engine, an electric motor for actuating the throttle valve, and a control unit for controlling the electric motor. The throttle valve is fixed to a valve shaft. The electric motor is connected to the valve shaft. The valve shaft is provided with a throttle opening sensor on the right end, and a mechanical, throttle valve actuating mechanism on the left end. A throttle cable is engaged with the mechanism, while being coupled to a throttle grip (acceleration controller) provided on a right one of a pair of handlebars.

Abstract: An element crack detecting apparatus for an oxygen sensor detects a sensor output voltage for an abnormality detection period after a fuel cut-off is started during operation of an engine. When the output voltage becomes negative, an abnormality counter is counted up. When the abnormality counter value reaches a determination value, it is determined that the element crack is present. The abnormality detection period is variably set in response to an engine rotational speed, an intake air quantity and the mixture state immediately before the fuel cut-off is effected. The determination value is variably set in response to the oxygen sensor temperature and the mixture state immediately before the fuel cut-off is effected. Further, the determination value is variably set in response to a magnitude of the negative voltage of the oxygen sensor.

Abstract: After initial combustion at the time of engine startup under very low temperature conditions, a fuel-injection start time point and a fuel-injection end time point are restricted to a period of time during which smoldering of an ignition plug is less prone to occur, to warm up the inside of a cylinder and increase engine speed. Thereafter, a fuel injection period is adjusted by gradually elongating it by reducing the restriction on the injection start time point and the injection end time point each time the engine speed exceeds a predetermined value in the course of the increase in the engine speed. In this way, the engines are made to reach a state where the engine can operate in a self-sustaining manner, before smoldering of the ignition plugs progresses after the initial combustion at the time of the engine startup under very low temperature conditions.

Abstract: A feedback correction coeficient used to perform feedback-control of the fuel injection amount based on the air-fuel ratio of exhaust gas is calculated. A concentration updating based value is set based on the deviation of the oscillation center of the feedback correction coefficiect, and a vapor concentration correction coefficient corresponding to the fuel concentration of purge gas is updated using the concentration updating base value. During the period where the fuel concentration of purge gas is expected to sharply decrease, the concentration updating base value is increased.

Abstract: The present invention is a supplementary control valve device including a valve body, which may be reversibly displaced in a guide, in the direction of the longitudinal axis, between an opening solenoid and a closing solenoid. The magnetic yoke of the opening solenoid includes at least one extension, with direct contact with a web, connected to the guide on the end thereof facing away from the extension.

Abstract: A method and apparatus adjust pilot fuel injection timing in relation to a main fuel injection timing into a piston cylinder of an operating gaseous-fuelled direct injection internal combustion engine using high levels of EGR. A set of engine parameters are monitored which determine engine load and engine speed and an indicator of EGR concentration within the intake charge. Pilot fuel timing relative to main fuel injection timing is then adjusted according to the engine parameters. High levels of EGR are shown to be tolerated with relatively limited penalties in relation to other emissions typically found with high EGR by reducing the relative injection timing the pilot fuel as compared to main fuel injection timing.

Abstract: A spring to ensure default opening is constituted by a single piano wire where a return spring with a larger coil diameter and a default spring with a smaller coil diameter are connected via a connection arm formed with a spring hook. The spring with a smaller coil diameter is inserted in the spring with a larger coil diameter thereby the springs are overlapped in an axial direction as a duplex-winding spring structure. Further, a magnetic sensor is provided in a position inside the both spring with a larger coil diameter and spring with a smaller coil diameter.

Abstract: A system and method for detecting and mitigating preignition for a multi-cylinder engine is provided. According to one aspect of the disclosure, a method is provided including identifying a preignition event at an affected cylinder; deactivating the affected cylinder during a deactivation period; initiating an accommodation system for one or more unaffected cylinders; and activating an indicator system.