Abstract: An injector apparatus (10) for injecting fluid under pressure into an associated chamber (32), the apparatus including a body (12), a first piston (14) moveable in the body, the first piston (14) defining a first working area facing an associated chamber (32), a high pressure piston (18, 118) defining a high pressure working area (182) facing a high pressure chamber (19, 119), the first working area being greater than the high pressure working area (182), the first piston (14) being operable to compress fluid in the high pressure chamber (19, 119), the first piston (14) further defining an injector orifice (76) through which the fluid can be injected into an associated chamber (32) from the high pressure chamber (19,119) and defining a valve seat (57), a valve member (92) selectively operable to engage the valve seat (57) to operably isolate the high pressure chamber (19, 119) from the injector orifice (76) and selectively operable to disengage the valve seat (57) to fluidly connect the high pressure chamber

Abstract: An embodiment system includes an ignition coil including a primary coil and a secondary coil, a high voltage battery selectively electrically connected the primary coil, a low voltage battery selectively electrically connected to the primary coil, and an electric and electronic element provided between the high voltage battery, the low voltage battery, and the primary coil of the ignition coil to selectively supply electric power of the high voltage battery or the low voltage battery to the primary coil.

Abstract: An alignment device for a ducted fuel injection system comprising a mounting block removably attachable to a duct of the ducted fuel injection system. The mounting block can include a passageway extending therethrough. The passageway can align with the duct when the mounting block is attached to the duct. The alignment device further comprises an imaging device configured to capture an image viewing through the duct toward an outlet of a fuel injector. A portion of the imaging device can extend in the passageway. The alignment device additionally comprises a centering structure configured to align a portion of the imaging device with a central axis of the duct. The image captured by the imaging device can be configured for use aligning a position of an outlet of a fuel injector with respect to a position of the duct.

Abstract: Systems and methods for estimating a temperature of an after treatment device in an exhaust system of an engine are described. In one example, the temperature is estimated during condition when an engine exits a fuel cut-out mode and excess fuel is delivered to the after treatment device for the purpose of increasing after treatment device efficiency.

Abstract: A method for controlling fuel injection aspects of a fuel system of an internal combustion engine includes determining a fuel injection strategy for each engine cycle including a pilot fuel injection, a main fuel injection, and a dwell time between the pilot and main fuel injections. The method also includes automatically adjusting the dwell time for each engine cycle based on a sensed ambient temperature and ambient pressure associated with the internal combustion engine.

Abstract: Methods and systems are provided for diagnosing a humidity sensor in an engine. In one example, a method may include heating intake air entering an intake passage of an engine using heat recirculated from an exhaust system of the engine. A response of the humidity sensor to the heating of the intake air may be used to assess an integrity of the humidity sensor.

Abstract: An internal combustion engine includes a fuel injection nozzle in which a nozzle hole that injects fuel is provided to be exposed to a combustion chamber from a cylinder head of the internal combustion engine, and a hollow duct in which an inlet and an outlet are exposed to the combustion chamber. The duct is provided to penetrate through an inside of the cylinder head so that fuel spray injected from the nozzle hole of the fuel injection nozzle passes from the inlet to the outlet. The duct is preferably configured so that a direction from the inlet to the outlet corresponds to a direction of the fuel spray injected from the nozzle hole.

Abstract: Disclosed is a method for the diagnosis of a digital valve in a fuel injection system. In the diagnosis, a diagnosis current is applied to the digital valve with an intensity and for a hold time that are predetermined by experiment on digital valves identified as being fault-free, this intensity and this time being recognized as being sufficient for an inflection on a curve of the closing current to be detected in the hold time. Measurements are taken at more than 3 kHz of the diagnosis current added to the induced current in the hold time. When an inflection on the current curve is detected in this hold time, it is concluded that the valve is working correctly. When no inflection on the curve is detected in this hold time, it is concluded that the valve is faulty.

Abstract: A duct assembly for a fuel injector of an engine includes a base and multiple duct bodies. The base includes a number of spaced apart receptacles. Each receptacle defines a cavity with a receptacle axis, a rotational engagement surface, and an axial engagement surface. The duct bodies are correspondingly secured within the cavities. Each duct body defines an axis and a duct extending along the axis to provide a passage for a fuel jet from the fuel injector. Each duct body defines an axial alignment surface engaging the axial engagement surface of the receptacle in which it is disposed to axially align the duct body along the receptacle axis of the corresponding receptacle.

Abstract: A controller for vehicle is provided. A determining section obtains fuel pressure in a delivery pipe and performs a rationality check for determining whether the obtained fuel pressure is within a normal range. The determining section shifts the normal range toward a high pressure side when a second index value of a vehicle outside temperature is higher than a first index value as compared with when the second index value is not higher than the first index value. The second index value is obtained when the determining section is activated. The first index value is stored in a nonvolatile memory before a main switch is turned off so that power supply is stopped.

Abstract: Methods and systems are provided for reducing errors in estimated fuel rail pressure incurred at the time of a scheduled injection event due to engine-driven cyclic fuel rail pressure changes. In one example, a pulse-width commanded during a scheduled injection event is determined as a function fuel rail pressure samples collected over a moving window that is customized for the corresponding fuel injector. In another example, the commanded pulse-width is determined as a function of an average fuel rail pressure sampled during a quiet zone of injector operation and predicted fuel rail pressure altering events occurring between the quiet zone and the scheduled injection event.

Abstract: In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is lower than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller outputs a control signal to a fuel injection valve so that a distribution ratio for the upper cavity is higher when the engine operates in the second state than when in the first state.

Abstract: A lubricity estimation device is applied to a fuel supply system that supplies a fuel to an internal combustion engine, and includes a mixing ratio estimation unit and a lubrication index calculation unit. The mixing ratio estimation unit estimates the mixing ratio of each of plural types of molecular structures included in the fuel. The lubrication index calculation unit calculates a lubrication index, representing the lubricity of an outer peripheral portion S1 of the piston of a fuel pump and an outer peripheral portion of the valve body of a fuel injection valve by the fuel, based on the mixing ratio estimated by the mixing ratio estimation unit.

Abstract: While providing the control such that the air excess ratio falls within the stoichiometric range, if the throttle opening degree control means determines that a value of the torque is smaller than A [Nm], the throttle opening degree control means provides a first control of controlling the opening degree of the intake throttle valve such that the output shaft rotates at a constant first rotation number. If the throttle opening degree control means determines that the value of the torque is larger than A [Nm], the throttle opening degree control means provides a second control of controlling the opening degree of the intake throttle valve such that the rotation number of the output shaft becomes larger.

Abstract: Methods and systems are provided for using compression heating to heat a cylinder piston before cylinder combustion is resumed. Cylinder heating is achieved using combinations of slow unfueled engine rotation where the engine cylinders are heated via compression stroke heating, and slow compressor rotation where the cylinders are heated via compression heating. One or more intake or exhaust heaters may be concurrently operated to expedite cylinder heating.

Abstract: A gas injector for injecting a gaseous fuel, in particular directly into a combustion chamber of an internal combustion engine, including: a valve closing element for opening or closing a pass-through opening, a valve body, and a sealing seat between the valve body and the valve closing element, in the case of a maximum lift of the valve closing element a flow cross section between the valve body and the valve closing element being smaller in the flow direction upstream from the sealing seat than a flow cross section between the valve closing element and the sealing seat and being smaller than a flow cross section in the flow direction downstream from the sealing seat.

Abstract: In a hybrid fuel supply system for the same high pressure supply pump used for gasoline direct injection (DI) is also used to supply the port injection (PI) system. For a given pumping stroke, fuel can be delivered only to the DI system, only to the PI system, or a first portion can be delivered to the DI system and a second portion delivered to the PI system. The pumping chamber always fills to maximum volume. Fuel metering for DI is by a control valve, which when closed delivers fuel into the DI system and when opened “spills” pumped fuel into the PI system. Any “spill” at high pressure opens a pressure regulating valve in the PI system that dumps fuel at excess pressure to a low pressure region to maintain the PI system at a constant target pressure.

Abstract: Systems and methods are provided for cooling an overheated engine using a combination of variable displacement engine (VDE) technology and direct injection technology. In one example, a method may include deactivating a subset of engine cylinders based on an engine temperature and directly injecting liquid fuel into the deactivated cylinders. In this way, an increased thermal conductivity of the liquid fuel compared to air decreases the engine temperature at a faster rate than when air-based engine cooling methods are used, thereby preventing overheating-related engine degradation.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, the engine system may be installed in a hybrid vehicle, and, in response to a request to restart the engine while the vehicle is being propelled via motor torque only, the engine may be rotated unfueled via the motor torque at less than cranking speed while at least partially opening a valve disposed in a passage coupled between the first exhaust manifold and the intake passage. In another example, in response to the request to restart the engine, all exhaust valves of a second set of exhaust valves coupled to the second exhaust manifold may be deactivated.

Abstract: A method for carrying out a gas exchange in a cylinder of an internal combustion engine is provided. The cylinder is connected to a gas line section via a valve. An actuator adjusts a gas pressure in the gas line section. The valve closes at a fixed point in time in a working cycle of the internal combustion engine in case of a constant torque of the internal combustion engine. The method includes the steps of recognizing a torque change request; determining a target value for the gas pressure in the gas line section in dependence on the torque change request; and determining a variable point in time for closing the valve as a result of the torque change request, wherein the variable point in time is shifted in the working cycle relative to the fixed point in time in dependence on the target value of the gas pressure.

Abstract: 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.

Abstract: An engine having at least a primary and secondary fuel supplies is configured to operate by determining a fueling mode for each of first and second groupings of cylinders, independently. A method, therefore, for operating the engine includes monitoring engine operating parameters with an electronic controller, determining an engine operating point based on the engine operating parameters, calculating a first operating mode of a first cylinder grouping based on the engine operating point, calculating a second operating mode of a second cylinder grouping based on the engine operating point, and selectively activating at least one of a diesel injector, a gaseous fuel injector and a spark device in each engine cylinder separately and selectively for each cylinder of the first and second cylinder grouping based on the engine operating point.

Abstract: Methods and systems are provided for adjusting engine cranking speed, fueling, and spark initiation to increase fuel vaporization during cold-start conditions. In one example, a method may include, during engine cold-start, cranking the engine at a lower speed relative to a nominal cranking speed while injecting fuel and disabling spark for a number of engine cycles, and after the completion of the number of engine cycle increasing the cranking speed and initiating spark.

Abstract: A distribution station includes a mobile trailer, a pump on the mobile trailer, a manifold on the mobile trailer and fluidly connected with the pump, a plurality of hoses connected with the manifold, a plurality of valves, each of the valves situated between the manifold and a respective one of the hoses, a plurality of fluid level sensors, each of the fluid level sensors being situated at an end of a respective one of the hoses, and a plurality of sensor communication lines. Each of the sensor communication lines is connected or connectable with a respective one of the fluid level sensors. Each of the sensor communication lines is routed with a respective one of the hoses.

Abstract: An injector, in particular a blow-in injector for gaseous fuel, including a first sealing element and a second sealing element, and in the closed state of the injector a first sealing region is configured between the first and second sealing element, at least one of the sealing elements having an elastic deformation region, the elastic deformation region being set apart from the sealing region between the first and second sealing element.

Abstract: In the interior of a resin mold portion that constitutes a fuel injection valve, an amplifying member to which a power source terminal and a signal terminal are connected, is provided. A signal transmitting unit, which outputs a detection signal from a sensor, is connected electrically to a substrate of the amplifying member. Further, the amplifying member is molded integrally when the resin mold portion is formed. In addition, a pressure inside a combustion chamber of an internal combustion engine, which is detected by the sensor, is output through the signal transmitting unit to the amplifying member, is amplified by the amplifying member, and is output externally from the signal terminal.

Abstract: A distribution station includes a mobile trailer, a pump on the mobile trailer, a manifold on the mobile trailer and fluidly connected with the pump, a plurality of hoses connected with the manifold, a plurality of valves, each of the valves situated between the manifold and a respective one of the hoses, a plurality of fluid level sensors, each of the fluid level sensors being situated at an end of a respective one of the hoses, and a plurality of sensor communication lines. Each of the sensor communication lines is connected or connectable with a respective one of the fluid level sensors. Each of the sensor communication lines is routed with a respective one of the hoses.

Abstract: A fuel injection control apparatus for an internal combustion engine having cylinders each of which includes a fuel injection valve and an intake valve, includes an intake valve controller, a parameter acquiring device, and an injection quantity correcting device. The intake valve controller performs an effective-compression-ratio reducing operation. The parameter acquiring device acquires a correction parameter including at least one of a rotational speed of the internal combustion engine, the valve closing timing of the intake valve, and an intake parameter indicating an intake fresh air amount flowing into the cylinders through an intake system. The injection quantity correcting device corrects a fuel injection quantity for the fuel injection valve in accordance with the acquired correction parameter to suppress variations among air/fuel ratios of air fuel mixtures in the cylinders while the intake valve controller performs the effective-compression-ratio reducing operation.

Abstract: A technique for fuel system protection for an internal combustion engine includes introducing a directly injected fuel into a combustion chamber through a direct fuel injector, introducing a fumigated fuel upstream of an intake valve, selectively operating the internal combustion engine with at least one of the directly injected fuel and the fumigated fuel, determining a temperature of the direct fuel injector as a first function of engine operating parameters, and performing a temperature mitigation technique when the temperature rises above a first predetermined value such that the temperature is maintained below a second predetermined value.

Abstract: A control device for an internal combustion engine is provided which can stabilize behavior when a fuel injection valve is opened, and reduce a variation in the amount of fuel injection of the fuel injection valve.

Abstract: A heat generation rate waveform of an internal combustion engine. A period from spark generated by an ignition plug to ignition of an air-fuel mixture is defined as an ignition delay period ? that is one of characteristic values of the heat generation rate waveform. When the ignition time FA of the air-fuel mixture is on the advance side of a compression top dead center of a piston (BTDC), the ignition delay period ? is estimated based on an in-cylinder fuel density ?fuel@SA at the spark time SA, and when the ignition time FA of the air-fuel mixture is on the delay side of the compression top dead center of the piston (ATDC), the ignition delay period ? is estimated based on an in-cylinder fuel density ?fuel@FA at the ignition time FA. Thus, the heat generation rate waveform is produced using the estimated ignition delay period ?.

Abstract: The vehicle traveling information recording device of the present invention comprises a camera unit for acquiring image information relating to outside of a vehicle; a recording unit for recording the image information from the camera unit; an abnormality detection unit for detecting an abnormal vehicle state; an auxiliary data detection unit for acquiring auxiliary data when the abnormality detection unit has detected an abnormality; and a control unit for combining the auxiliary data with the image information in the recording unit when the abnormality detection unit has detected the abnormality, and recording image information after the combination related to abnormality detection.

Abstract: An internal combustion engine, including a combustion chamber with a first aperture; a compression chamber with a second aperture; and a crossover valve comprising an internal chamber, first and second valve seats, a valve head, and first and second valve faces on the valve head, wherein the first aperture allows fluid communication between the combustion chamber and the internal chamber, the second aperture allows fluid communication between the compression chamber and the internal chamber, the first valve face couples to the first valve seat to occlude the first aperture, and the second valve face couples to the second valve seat to occlude the second aperture.

Abstract: An engine system is disclosed. The engine system may have a first bank of cylinders, a second bank of cylinders, a first intake manifold, and a second intake manifold. The engine system may also have a first exhaust manifold connecting the first bank of cylinders to the first and second intake manifolds, a second exhaust manifold connecting the second bank of cylinders to the atmosphere, a plurality of injectors, and a controller. The controller may be configured to inhibit the plurality of injectors associated with a first cylinder subset of the first and second banks of cylinders from firing for a first period of time spanning multiple engine cycles. The controller may also be configured to selectively inhibit the plurality of injectors associated with a second cylinder subset of the first and second banks of cylinders from firing for a second period of time following the first period of time.

Abstract: A waveform detector detects a variation in fuel pressure based on a detection value of a fuel pressure sensor as a fuel pressure waveform. A determining portion determines whether an interval between injections is zero or smaller than a predetermined value based on the detected fuel pressure waveform when multi-step-injection is performed. A correcting portion corrects an injection command signal indicative of an injection start timing and an injection end timing corresponding to a target injection state in a manner that the interval is increased when the interval is determined to be zero or smaller than the predetermined value.

Abstract: Various methods and systems are provided for supplying gaseous natural gas to a rail vehicle. In one embodiment, a method of receiving fuel for use by a first vehicle comprises sending a request from the first vehicle to a remote liquid fuel container to convert a portion of the fuel in the liquid fuel container that is in a first, liquid phase from the first, liquid phase to a second, gaseous phase.

Abstract: In a nozzle, in a cross section including an axis of a nozzle body, a side surface and a seat surface are both smoothly connected to an arc of a circle inscribing both the side surface and the seat surface. A part of a needle which is adjacent to a tip end side of a seat portion is a cone having a diameter reduced toward a tip end side of the cone in the axial direction. Thus, no corner is on the seat surface or the side surface, and the two surfaces form one curved surface. Since a cavitation generated in a sack chamber can be reduced, even when an injection quantity is significantly small such that an injection port does not throttle an injection flow, a flow coefficient of the injection flow is improved and a penetration of a spray of the fuel can be maintained.

Abstract: A method for operating an internal combustion engine involves using an injection valve to post-inject fuel into at least one cylinder of the internal combustion engine in order to help regenerate a particulate filter that is arranged in an exhaust system of the internal combustion engine, downstream of an oxidation catalyst. A closing moment of a discharge valve of a cylinder of the internal combustion engine is advanced when the temperature of the oxidation catalyst is in a first temperature range, and the post-injections are performed when the temperature of the oxidation catalyst is in a second temperature range, an upper limit of the first temperature range having a lower value that an upper limit of the second temperature range.

Abstract: A method for controlling an internal combustion engine based on the amount of un-burned fuel dissolved in the engine oil, and returned into the manifold through the PCV valve as the engine oil temperature rises via adjusting fuel injection into a cylinder from a fuel injector, in a fuel delivery system. The fuel dilution in engine oil and the amount of fuel entering the intake manifold through the PCV valve can be determined based on one or more of oil volume, fuel composition (e.g., ethanol content), oil temperature, engine temperature, engine speed, engine load, engine run time, injected fuel mass, and exhaust gas composition.

Abstract: Methods are provided for controlling a solenoid spill valve of a direct injection fuel pump, wherein the solenoid spill valve is energized and de-energized according to certain conditions. An example control strategy is provided for operating the direct injection fuel pump when fuel vapor is detected at an inlet of the direct injection fuel pump. To ensure pump effectiveness during the presence of fuel vapor, the solenoid spill valve may be maintained energized for a minimum angular duration past a top-dead-center position of a piston in the direct injection fuel pump.

Abstract: An operating mode for an internal combustion engine, in particular a directly injected internal combustion engine having a plurality of combustion chambers, in particular for a directly injected gasoline engine, e.g. for a motor vehicle, having low NOx combustion (NAV). During the NAV operating mode that is the subject matter of this invention, at an ignition point (ZZP) a largely homogeneous, lean fuel/exhaust gas/air mixture having a combustion air ratio of ??1 in the respective combustion chamber is spark ignited by an ignition device, whereby the flame front combustion initiated by the ignition device (FFV) transitions to a controlled auto-ignition (RZV). The NAV operating mode enables a controlled auto-ignition to be performed in an engine load range in which a pure RZV operating mode is no longer stable enough to be implemented.

Abstract: A method for operating a hybrid drive train involves operating an internal combustion engine using a low-NOx operating method in a range of low and average rotational speeds and/or loads, and operating the internal combustion engine using a spark ignition operating method in a range of higher rotational speeds and/or loads.

Abstract: A fuel assembly and a method of providing fuel is disclosed. The fuel assembly includes a frame, a first fuel storage tank sized to fit within the frame and configured to store one of a liquid and a gaseous fuel, and a fuel control assembly configured to regulate delivery of the gaseous fuel to an external power unit. The fuel control assembly includes a first fuel assembly memory module having stored thereon identifying information of the interchangeable fuel assembly.

Abstract: A heat shield structure includes an engine body having an exhaust manifold at its side portion, a fuel pump arranged above the engine body, and an engine cover. The engine cover includes a covering portion and a heat shield portion. The covering portion covers the fuel pump and the engine body from above. The heat shield portion protrudes downward from the covering portion. The heat shield portion partitions a space above the engine body and a space above the exhaust manifold from each other. The engine cover has an air guide passage between the engine body and the covering portion, the air guide passage extending from a front side of a vehicle toward the fuel pump.

Abstract: A control device for direct injection gasoline engines includes a fuel injection control part (engine control device) composed to control a fuel injection aspect of an injector. The fuel injection control part changes an injection mode of the injector by changing the lift amount of the injector and the injection interval of the fuel respectively. The fuel injection control part switches between a first injection mode, which includes multiple times of the fuel injection with the small lift amount of the injector and the small interval of the fuel injection, and a second injection mode, which includes multiple times of the fuel injection with the bigger lift amount of the injector and the larger interval of the fuel injection than those of the first injection mode, according to an operating state of the engine body.

Abstract: The present disclosure is directed to injectors with integrated igniters providing efficient injection, ignition, and complete combustion of various types of fuels. These integrated injectors/igniters can include, for example, multiple drivers used to shape charges, controllers used to modify operations based on ionization parameters, and so on.

Abstract: Systems and methods are disclosed that include operating an isothermal compression based combustion (IsoC) engine by injecting isothermally compressed air into a combustion engine immediately prior to a combustion event in order to increase the efficiency of the engine, improve emissions, and substantially eliminate autoignition and associated design constraints. The IsoC engine utilizes an intercooled compressor to isothermally compress air that is stored in a plurality of capacitance tanks prior to delivery of the compressed air to the combustion engine. The IsoC engine allows combustion to be selectively terminated to increase fuel efficiency, thereby resulting in a hybrid compressed air-motor and internal combustion operated IsoC engine.

Abstract: A control apparatus for an internal combustion engine is capable of switching a combustion mode between a spark ignition combustion mode for combusting a mixture formed in a combustion chamber with spark ignition and a compression ignition combustion mode for combusting the mixture with compression ignition. When the combustion mode is switched from the spark ignition combustion mode to the compression ignition combustion mode, in an internal EGR control for keeping a part of a burnt gas generated by the combustion remaining as an internal EGR in the combustion chamber, an internal EGR amount of the internal EGR is increased, an ignition timing is advanced, and a fuel injection amount is decreased so that an oxygen density contained in the internal EGR used to form the mixture increases.

Abstract: An internal combustion engine having six in-line piston and cylinder assemblies providing a center pair, an intermediate pair and an outer pair, each pair having crankshaft connected pistons mounted in cylinders through simultaneous repetitive strokes four of which together constitute simultaneous repetitive cycles including a drive event injectors selectively (1) in a (Mode 1) to inject fuel in both cylinders and (2) in a (Mode 2) to inject fuel in only one cylinder, the cylinders of the center pair being intercommunicated by a passage. The effect of skipping an injection in (Mode 2) in the center pair is a pair of shared power drive events and in the other pairs the effect in one of the cylinders is a directly fired power drive shaft and the effect in the other cylinder is deactivation and a method of operating the engine in a vehicle.

Abstract: An internal combustion engine having two banks of four piston and cylinder assemblies arranged in an inverted V configuration so that there are four pairs of assemblies each pair having cylinders with adjacent combustion chambers intercommunicated by a passage extending therebetween. Crank shaft driven pistons in said cylinders movable within the combustion chambers thereof through successive cycles each including a compression stroke followed immediately by a power drive stroke. Computer controlled fuel injectors are capable of being selectively controlled to operate either to inject fuel into (1) both cylinders of a pair to establish therein a double fire single expansion mode, or (2) into only one cylinder of a pair to establish therein a single fire double expansion mode with the one cylinder receiving the injection being alternated between the pair every predetermined number of piston cycles.