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.

Various methods and systems are provided for maintaining combustion stability in a multi-fuel engine. In one example, a system comprises a first fuel system to deliver liquid fuel to at least one cylinder of an engine, a second fuel system to deliver gaseous fuel to the at least one cylinder, and a controller. The controller is configured to supply the gaseous fuel to the at least one cylinder, inject the liquid fuel to the at least one cylinder thereby to ignite the liquid fuel and the gaseous fuel in the at least one cylinder via compression-ignition, and adjust an amount of the gaseous fuel relative to an amount of the liquid fuel based on a measured parameter associated with auto-ignition of end gases subsequent to the compression-ignition of the liquid fuel.

An engine (21) including a cylinder internal pressure sensor (63), a torque sensor (64), and an engine control device (73). The cylinder internal pressure sensor (63) detects a cylinder internal pressure. The torque sensor (64) detects an engine load. The engine control device (73) receives a detection result of the cylinder internal pressure sensor (63) and a detection result of the torque sensor (64). If the load detected by the torque sensor (64) is zero (no load) and the cylinder internal pressure obtained from the detection result of the cylinder internal pressure sensor (63) is greater than or equal to a threshold, the engine control device (73) determines that an abnormality occurs in detection by the torque sensor (64).

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.

An engine control system comprises a balancing arrangement together with a knock mitigation controller configured to implement a knock mitigation procedure wherein an offset input value (V.sub.I) is applied to the balancing algorithm. The offset input value (V.sub.I) may cause the balancing algorithm to adjust the control output (O.sub.1) for the respective one of the combustion chambers to progressively vary the fuel supply or ignition timing for the affected cylinder to mitigate the knock condition. Alternatively, the controller may generate an offset output value (V.sub.O) to more rapidly vary the fuel supply or ignition timing, with the offset input value (V.sub.I) being selected for example to compensate for the resulting change in the control input (I.sub.1) from the cylinder to the balancing algorithm, or to provide additional, more gradual adjustment to further mitigate the knock condition.

The invention relates to a method of controlling operation of an ICE arrangement (1), comprising acquiring (100) a first signal indicative of a required torque; acquiring (102) a second signal indicative of a temperature (T) of an EATS (23); and when the second signal indicates that the temperature (T) of the EATS (23) is lower than a predefined first threshold temperature (T.sub.1): determining (108; 118) an amount of second fuel (17) needed to deliver the required torque; supplying the amount of second fuel (17); controlling (112; 122) an inlet valve (19) to allow flow of a second fuel-air mix into the cylinder (3); injecting first fuel (13) into the cylinder (3) when the second fuel-air mix is compressed by the piston (9), resulting in flame propagation ignition of the second fuel-air mix; and controlling (116; 126) and outlet valve (21) to allow flow of exhaust from the cylinder (3) during an exhaust stroke (ES) of the piston (9).

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.

The invention concerns a method of operating a compression ignition engine (10) fuelled with a combination of a hydrocarbon fuel and hydrogen. The method comprises: during a cold start, fuelling the engine with the hydrocarbon fuel alone, or with the hydrocarbon fuel and a reduced proportion of hydrogen compared with warm miming conditions, and increasing the proportion of hydrogen used to fuel the engine as it warms up whilst running.

Various methods and systems are provided for adjusting fueling to groups of cylinders of an engine based on individual cylinder knock sensor outputs. As one example, a system for an engine includes: a controller with computer readable instructions stored on non-transitory memory that when executed during operation of the engine cause the controller to: deliver natural gas and diesel fuel to a first group of cylinders at amounts that produce a common, first substitution ratio of natural gas; deliver natural gas and diesel fuel to a second group of cylinders at amounts that produce a common, second substitution ratio of natural gas; and change a makeup of each of the first group of cylinders and the second group of cylinders based on individual knock sensor outputs of each cylinder of the first group of cylinders and the second group of cylinders.

Systems, methods and apparatus for controlling operation of dual fuel engines are disclosed that regulate the fuelling amounts provided by a first fuel and a second fuel during operation of the engine. The first fuel can be a liquid fuel and the second fuel can be a gaseous fuel. The fuelling amounts are controlled to improve operational outcomes of the duel fuel engine.