A method for starting a gaseous fuel internal combustion engine is disclosed. According to the disclosed method, the engine is rotated using a start device until a first speed threshold is reached. After reaching the first speed threshold, pilot fuel is supplied to a plurality of cylinders of the engine to combust the same. After performing an ignition health check, gaseous fuel is supplied to all or a relatively large number of cylinders to start accelerating the engine up to a second speed threshold.

An engine including an exhaust bypass valve and an intake bypass valve. The exhaust bypass valve is disposed in an exhaust bypass channel connecting an outlet of an exhaust manifold and an exhaust outlet of a turbocharger to each other. The intake bypass valve is disposed in an intake bypass channel connecting an inlet of an intake manifold and an inlet of the turbocharger. An intake pressure sensor detects a pressure of the intake manifold. If an instruction value indicating an upper limit or a lower limit of the valve opening degree of the intake bypass valve is continuously output for a predetermined time or more, an engine control device determines that an abnormality occurs in at least one of the exhaust bypass valve and the intake bypass valve.

A method of controlling a dual fuel engine system includes adjusting a phasing control parameter such as air-fuel ratio (AFR), based on a phasing signal to limit an error in a phasing of combustion of gaseous fuel. The cylinder is switched to a dual fuel liquid pilot-ignited mode by commanding direct injection of an early pilot shot of liquid fuel, based on the adjustment to the phasing control parameter, and production of a spark to ignite gaseous fuel in the cylinder. Switching the cylinder to the dual fuel liquid pilot-ignited mode is completed by commanding direct injection of an early pilot shot and a second pilot shot of liquid fuel to ignite gaseous fuel in response to combustion of the early and second pilot shots in the cylinder.

An engine device including an intake manifold configured to supply air into a cylinder; an exhaust manifold configured to output exhaust gas from the cylinder; a gas injector which mixes a gaseous fuel with the air supplied from the intake manifold; and a main fuel injection valve configured to inject a liquid fuel into the cylinder for combustion. At the time of switching from a gas mode in which the gaseous fuel is supplied into the cylinder to a diesel mode in which the liquid fuel is supplied into the cylinder, a supply-start timing of the liquid fuel is delayed relative to a supply-stop timing of the gaseous fuel.

A gaseous fuel supply system for an internal combustion engine may include a storage tank for storing liquefied gaseous fuel and supplying the fuel to the engine. The system may also include a liquid level sensor for measuring a level value of the liquefied gaseous fuel in the storage tank and a pressure sensor for measuring a pressure value of gaseous fuel in the fuel supply system. The system may further include a controller. The controller may be configured to: monitor a pressure signal of the pressure sensor indicating the pressure value and a tank level signal of the liquid level sensor indicating the level value; store the level value when the pressure value indicates the storage tank is empty; store the level value when the pressure value or the level value indicates the storage tank is full; and determine a calibrated level range based on the stored level values.

An engine including an exhaust bypass valve and an intake bypass valve. The exhaust bypass valve is disposed in an exhaust bypass channel connecting an outlet of an exhaust manifold and an exhaust outlet of a turbocharger to each other. The intake bypass valve is disposed in an intake bypass channel connecting an inlet of an intake manifold and an inlet of the turbocharger. An intake pressure sensor detects a pressure of the intake manifold. If an instruction value indicating an upper limit or a lower limit of the valve opening degree of the intake bypass valve is continuously output for a predetermined time or more, an engine control device determines that an abnormality occurs in at least one of the exhaust bypass valve and the intake bypass valve.

A gaseous fuel supply system for an internal combustion engine may include a storage tank for storing liquefied gaseous fuel and supplying the fuel to the engine. The system may also include a liquid level sensor for measuring a level value of the liquefied gaseous fuel in the storage tank and a pressure sensor for measuring a pressure value of gaseous fuel in the fuel supply system. The system may further include a controller. The controller may be configured to: monitor a pressure signal of the pressure sensor indicating the pressure value and a tank level signal of the liquid level sensor indicating the level value; store the level value when the pressure value indicates the storage tank is empty; store the level value when the pressure value or the level value indicates the storage tank is full; and determine a calibrated level range based on the stored level values.

The invention relates to a fuel injector arrangement (1) comprising a number of fluid supply paths (29, 31, 39), namely, a first (29), a second (31) and a third fluid supply path (39). The fuel injector arrangement (1) has a first switching device (43) in the second fluid supply path (31). Said first switching device, controlled by the fluid pressure in the third fluid supply path (39), opens or blocks the second fluid supply path (31). The fuel injector arrangement (1) has a second switching device (49) in the first fluid supply path (29). Said second switching device, controlled by the fluid pressure downstream of the first switching device (43) in the second fluid supply path (31), opens or blocks the first fluid supply path (29).

A method for operating an internal combustion engine having at least one fuel injector that is activated for opening and closing via a solenoid valve of a respective fuel injector. Commencing with the activation of the fuel injector for opening, structure-borne sound waves emitted by the fuel injector over the time are detected by measurement. A structure-borne sound wave signal detected by measurement over the time is evaluated such that dependent on the amount of at least one maximum of the structure-borne sound wave signal and/or dependent on the number of the maximums of the structure-borne sound wave signal and/or in the presence of multiple maximums dependent on the time sequence and/or on the amount of the maximums, an operating state of the respective fuel injector is deduced.

Dual-fuel internal combustion engine with at least two combustion chambers which have a different distance from at least one gas mixer for producing a gas-air mixture, whereby an inlet valve for the gas-air mixture and an injector for liquid fuel is assigned to each of the combustion chambers, and a control device is provided which is configured in a change-over mode to change an amount of energy supplied to the at least two combustion chambers through the gas-air mixture in a first direction, and to change an amount of liquid fuel supplied to the at least two combustion chambers in an opposite, second direction, whereby the control device is designed to determine a time for the change of the amount of liquid fuel in the second direction for each of the at least two combustion chambers according to the distance of the respective combustion chamber from the at least one gas mixer.