Abstract: A system according the principles of the present disclosure includes a torque determination module and a torque limit module. The torque determination module determines a first torque that prevents an engine from stalling. The torque limit module limits engine torque based on the first torque when a driver actuates an accelerator pedal from a first position in which the accelerator pedal is not depressed to a second position in which the accelerator pedal is depressed.

Abstract: Injector drift for a diesel engine are detected by reconfiguration of injection patterns from one pattern into a pattern with a different number of pulse points while attempting to hold total fuel injected constant. If a particular injector is subject to drift then changes in the pulse pattern result in an increase or decrease in fuel injected and consequential variations in engine speed. By applying alternating injection patterns at constant fuel demand and allowing engine speed time to stabilize, a rhythmic variation in engine speed/torque will appear which can be detected using one of a number of techniques.

Abstract: A method for operating an internal combustion engine in which a speed-based feature of the internal combustion engine, which is correlated with an indicated mean effective pressure of the fuel, is determined during the warm-up of the internal combustion engine and an ideal fuel quantity, which is to be injected into at least one combustion chamber of the internal combustion engine during the warm-up, is ascertained therefrom.

Abstract: In an engine having a plurality of cylinders in which a plurality of fuel injection valves are provided respectively, fuel is injected at a predetermined injection ratio, and an abnormality of air-fuel ratio variation is detected. If a fuel injection amount of at least one of the plurality of the fuel injection valves is smaller than a predetermined reference value, the fuel injection amount is increased so as to become equal to or larger than the reference value.

Abstract: When the temperature in a cylinder of an engine is low, the fuel injection amount of fuel that has a low vapor pressure and is less likely to be vaporized is increased, and the fuel injection amount of fuel that has a high vapor pressure and is more likely to be vaporized is reduced, so that the start timing of the engine can be kept constant. When the temperature in the cylinder is high, the fuel injection amount of the fuel that has a low vapor pressure and is more likely to be decomposed is reduced, and the fuel that has a high vapor pressure and is less likely to be burned (decomposed) is increased, so that the start timing of the engine can be kept constant. Thus, the start timing of the engine is kept constant irrespective of the fuel property, and deterioration of the drivability can be curbed.

Abstract: A method for operating a fuel system for an internal combustion engine having a metering device, an electrical actuating device, and a valve element includes: activating the electrical actuating device in at least one first cycle in such a way that the valve element switches into a second position corresponding to an open metering device; activating the electrical actuating device in at least one second cycle in such a way that the electrical actuating device is activated from activation to activation, with activation energy which decreases gradually, until a limiting case is reached in which the valve element only just or just no longer switches into the second position; ascertaining a first activation energy, which corresponds to the limiting case; and subsequently activating the actuating device, taking the first activation energy into account.

Abstract: A fuel injection amount control apparatus calculates as a proportional term a value obtained by multiplying by a proportional gain Kp a deviation DVoxslow between a downstream side target value Voxsref and an output value Voxs of a downstream side air-fuel ratio sensor disposed downstream of a catalyst. The control apparatus calculates a time integrated value SDVoxslow by integrating a value obtained by multiplying by a predetermined adjustment gain K the deviation DVoxslow, calculates a value that is commensurate with the time integrated value SDVoxslow as an integral term Ki×SDVoxslow, and obtains the integral term Ki×SDVoxslow as a sub-FB learned value KSFBg. The control apparatus sets the proportional gain Kp at a small value after the sub-FB learned value KSFBg is determined to have converged, and sets the adjustment gain K at a small value after the sub-FB learned value KSFBg is determined to have converged.

Abstract: A method for operating an internal combustion engine, having an exhaust gas turbocharger, during a load change of the internal combustion engine, includes initiation of a closing process of a throttle valve of the internal combustion engine, disposed in an induction tract or intake section of the internal combustion engine, as a function of an air pressure which is present upstream of the throttle valve, in such a way that the air pressure always falls short of a surge limit or pumping limit of a compressor, disposed in the induction tract, of the exhaust gas turbocharger. A staged or stepped reduction in a torque of the internal combustion engine is performed by shutting off fuel injections at predetermined cylinders of the internal combustion engine. An internal combustion engine with an exhaust gas turbocharger is also provided.

Abstract: A method to control a non-linear system includes operating a learning cycle to approximate characteristics of the system and, once the learning cycle is complete, operating the system based upon the characteristics. The learning cycle includes monitoring operation of the system, approximating the characteristics of the system with a recursive least squares approximation based upon the monitored operation, comparing variance of the operation to a threshold variance, and completing the learning cycle based upon the variance exceeding the threshold variance.

Abstract: A system and attendant structural assembly operative to establish a coordinated mixture of gaseous and distillate fuels for an engine including an electronic control unit (ECU) operative to monitor predetermined engine data determinative of engine fuel requirements and structured to regulate ratios of the gaseous and distillate fuel of an operative fuel mixture for the engine. The system and assembly includes at least one mixing assembly comprising an integrated throttle body and air gas mixer directly connected to one another, wherein the throttle body is disposed in fluid communication with a pressurized gaseous fuel supply and the air gas mixer is disposed in fluid communication with a flow of intake air to a combustion section of the engine. In use, the throttle body is structured to direct a variable gaseous fuel flow directly to the air gas mixer for dispensing into the intake air flow to the combustion section.

Abstract: An air-fuel ratio control system of an internal combustion engine comprises a fuel amount determiner for determining a fuel command value. The fuel amount determiner has a feedback control mode in which the fuel amount determiner determines a running state reference coefficient corresponding to a running state detected by a running state detector based on a first correspondence stored in the memory, determines a running state compensation coefficient corresponding to the running state detected by the running state detector based on a second correspondence stored in the memory, determines a feedback compensation coefficient used to cause an air-fuel ratio to reach a value closer to a theoretical air-fuel ratio based on an output of the air-fuel ratio sensor, and determines the fuel command value using a formula including the determined running state reference coefficient, the determined running state compensation coefficient, and the determined feedback compensation coefficient.

Abstract: At the time of an engine start while the vehicle is driving, when a required vehicle driving force (TRQ) is smaller than or equal to a predetermined value (TRQth), an electronic control unit (20) estimates that the degree of deformation of a mount (11) is smaller than or equal to a predetermined degree and sets a second-cycle fuel injection amount (Q2) so as to be larger than a first-cycle fuel injection amount (Q1) at the time of the engine start. On the other hand, when the required vehicle driving force (TRQ) is larger than the predetermined value (TRQth), the electronic control unit (20) estimates that the degree of deformation of the mount (11) is larger than the predetermined degree and sets the first-cycle fuel injection amount (Q1) so as to be larger than the second-cycle fuel injection amount (Q2) at the time of the engine start.

Abstract: An apparatus for detecting an abnormal air-fuel ratio variation among cylinders of a multi-cylinder internal combustion engine includes: a detecting unit detecting the abnormal air-fuel ratio variation on the basis of output fluctuations of at least one predetermined target cylinder when fuel injection amount changing control for changing a fuel injection amount of the target cylinder by a predetermined amount is executed; and an air-fuel ratio control unit causing an air-fuel ratio detected on the basis of a signal output from an air-fuel ratio sensor provided in an exhaust passage to follow a predetermined target air-fuel ratio. When the fuel injection amount changing control is executed, a target air-fuel ratio in the air-fuel ratio feedback control is shifted from the predetermined target air-fuel ratio by an amount corresponding to an amount of change of the fuel injection amount of the target cylinder in the fuel injection amount changing control.

Abstract: Methods and systems are provided for identifying and indicating degradation of an engine cylinder spark plug. In response to a cylinder misfire event during selected engine operating conditions, followed by an occurrence of a threshold number and/or rate of pre-ignition events in the same cylinder, a controller may determine that the spark plug is degraded. The controller may limit combustion in the cylinder in response to the degradation. Additionally, cylinder pre-ignition mitigating steps may be taken.

Abstract: Invention suppresses deterioration of emission if there is air-fuel ratio imbalance among cylinders.

Abstract: A method for controlling a pressure control valve which controls the pressure in a high-pressure accumulator of a fuel metering system of an internal combustion engine, fuel being metered into the combustion chambers of the internal combustion engine from the high-pressure accumulator, and the pressure control valve being connected to the high-pressure accumulator and controlling the outflow of fuel from the high-pressure accumulator into a low-pressure accumulator, and it being provided, in particular, that in the case of a closed pressure control valve, the energization of the pressure control valve is reduced until the pressure control valve opens, and a close offset input is ascertained based on the energization present at the opening of the pressure control valve.

Abstract: A control apparatus for an internal combustion engine includes a fuel injection portion that carries out fuel injection for the internal combustion engine, a recirculation portion that recirculates to an intake system evaporative gas of injected fuel that has been mixed with lubricating oil for the internal combustion engine, a parameter acquisition portion that acquires a fuel mixture parameter corresponding to an amount of fuel that has been mixed with the lubricating oil, an engine stop portion that performs engine stop control to temporarily stop the internal combustion engine when a predetermined stop condition is fulfilled, and a stop condition correction portion that corrects a stop condition of the engine stop control on the basis of at least the fuel mixture parameter.

Abstract: The purpose of the present invention is to suppress, in an internal combustion engine in which two injectors are disposed in a line upstream and downstream in an intake pipe, adhesion of deposits to the downstream-side injector. In order to suppress such adhesion, a fuel injection control device according to one embodiment of the present invention operates both injectors together when a required fuel injection amount is equal to or greater than a reference value. The reference value is set to a value equal to or greater than the sum of lower limit injection amounts of the injectors. In such case, the fuel injection control device adjusts the proportion of fuel injected from the injector disposed downstream in the intake pipe to be greater than the proportion of fuel injected from the injector disposed upstream in the intake pipe.

Abstract: An estimated fuel consumption quantity corresponding to a fuel injection timing of an engine is reduced or set to zero if failure of the corresponding injector has been detected. A pump control apparatus controls a fuel supply pump to maintain the pressure in a common rail at a target value by control of a command delivery quantity supplied from the pump to the common rail in correspondence with each injection timing. Each command delivery quantity is determined based on a necessary delivery quantity and on a feedback quantity, which is derived from a difference between previously obtained values of command delivery quantity and of a corresponding actual delivery quantity from the pump. Prior to the injection, a pressure compensation quantity is calculated, as a fuel quantity required to bring the fuel rail pressure to the target pressure value, and is added to the fuel consumption quantity to obtain the necessary delivery quantity.

Abstract: A control apparatus for an internal combustion engine where the inside of a combustion chamber is divided into a layer of internal EGR gas and a combustible layer to perform stratified combustion. In a port-injected engine equipped with first and second intake valves, the opening timing of the first intake valve is set before a top dead center (TDC) and the opening timing of the second intake valve is set after the TDC, and the closing timings of the first intake valve and the second intake valve are set after a bottom dead center. Then, fuel injection toward the first intake valve is started after the EGR gas, which was blown back to the intake port upstream of the first intake valve, is drawn into the combustion chamber after the top dead center.

Abstract: A controlling method for a flame jet ignition engine includes: a setting step of setting a map as a low load operation region, a medium load operation region, and a high load operation region depending on a load which is measured at the time of the driving of the engine; and a first burning step of performing burning by being controlled with an air-fuel ratio more lean than a theoretical air-fuel ratio and reducing NOx while increasing and compensating for a burning rate depending on burning of the jet ignition apparatus, at the time of entering the low load operation region and the medium load operation region.

Abstract: A device for controlling fuel injection in an internal combustion engine of an automobile, the internal combustion engine being connected at an inlet thereof to a fresh air intake pipe and at an outlet thereof to an exhaust gas discharge pipe including a catalytic converter, an exhaust gas partial recirculation circuit connecting the discharge pipe to the fresh air intake pipe. The device includes a mechanism determining the amount of unburned fuel in the exhaust gases, a mechanism determining the amount of fresh air taken into the internal combustion engine, and an electronic controller determining the amount of fuel to be injected depending on signals received of the determined amount of unburned fuel and the determined amount of fresh air taken in.

Abstract: In a method for individually correcting injection quantities and/or times (mf1, mf2, mf . . . ; ti1, ti2, ti . . . ) in particular for a ballistic operating range of a fuel injector (1, 2, . . . ), a quantity deviation of an actual injection quantity (mf1, mf2, mf . . . ) from a nominal injection quantity (mfnom) of the fuel injector (1, 2, . . . ) during operation of the fuel injector (1, 2, . . . ) is determined, and a typical injection characteristic (fup1, fup2, fup . . . ) of the fuel injector (1, 2, . . . ) is adapted to a nominal injection characteristic (fupnom) based on the quantity deviation. Furthermore, a controller, in particular an engine controller may implement the above method.

Abstract: Methods and systems are described for conserving fuel used by an engine. In some embodiments a control module processes a user-provided input, as a first function, into a second function. The second function can be used to direct the engine with a directive output power. The directive output power may have regions equal to, greater than, and/or less than what the power output would be if the engine were controlled using the user-provided input.

Abstract: An engine rotational speed control device (4) includes a noise removal processing unit (6) which corrects a command value, wherein the noise removal processing unit (6) is configured to set a current first output value (B(i)) to be identical to a previous first output value (B(i?1)) in a case where, in a latest step group, the number of successive increase steps is smaller than a first predetermined number (n) and the number of successive decrease steps is smaller than the first predetermined number (n), the increase step is a step in which a current first input value (A(i)) is greater than the previous first output value (B(i?1)) by a first set width (n) or more, and the decrease step is a step in which the current first input value (A(i)) is smaller than the previous first output value (B(i)) by the first set width (n) or more.

Abstract: A method for determining the quantity of fuel flowing through a fuel injector. The fuel injector has an electric heating device for heating the fuel and a temperature-measuring device for measuring the temperature of the heated fuel. The method includes (a) applying a predetermined electrical heating power to the electric heating device, (b) measuring an increase in the temperature of the fuel as a consequence of the heating power, and (c) determining the quantity of fuel flowing through the fuel injector on the basis of the applied electrical heating power and the measured increase in the temperature. A method for equalizing the fuel feed at at least two cylinders of an internal combustion engine utilizes the method for determining the quantity of fuel flowing through a fuel injector. An engine controller and a computer program carry out the specified methods.

Abstract: In a method for operating a fuel injector, a transition range of the characteristics curve of the injector is detected individually and adapted continuously, so that a monotonous characteristics curve is formed, with whose aid high metering precision of the injector is achieved.

Abstract: A control apparatus for operating a fuel injector is provided. The control apparatus includes an electronic control unit configured to: identify when the engine is running under a fuel cut-off condition, and then perform a learning procedure to determine an actual value of energizing time that causes the fuel injector to inject a target fuel quantity. The learning procedure provides for the electronic control unit to perform several test injections with different energizing time values and measure an engine torque value caused by the test injection. The measured engine torque values and their correspondent energizing time values are used to extrapolate the actual value of the energizing time as the value that corresponds to a reference value of engine torque that is consistent with the target fuel quantity.

Abstract: A control apparatus is disclosed for operating a fuel injector of an internal combustion engine. The control apparatus includes an Electronic Control Unit configured to: perform a first calculation task in order to calculate a set of Start Of Injection values (SOIi) of a train of injections, calculate an angular position (DIAngPos) of the crankshaft defining the start of a second calculation task, and perform the second calculation task in order to calculate a set of values (ETi) of the energizing time of the injections of the train. The angular position (DIAngPos) is calculated as a function of the Start Of Injection value (FirstSOI) of the first injection of the train as calculated by the first calculation task.

Abstract: Valve stopping control is performed that changes an operating state of an intake valve and an exhaust valve to a closed-valve stopped state when executing a fuel-cut operation. A device is provided that sets an in-cylinder return-time target air-fuel ratio for an initial two return cycles when returning from a fuel-cut operation. The return-time target air-fuel ratio is set so that respective air-fuel ratios of air-fuel mixtures of fuel and air injected into the same cylinder for respective cycles during the initial return cycles each become values that fall within a combustible range, and so that even if a total amount of fuel injected into the same cylinder for the initial return cycles is supplied into the cylinder during an arbitrary single cycle, the air-fuel ratio of the air-fuel mixture of the total amount of fuel and air becomes a value that falls within the combustible range.

Abstract: A system and method for controlling fuel injection and a fuel injection system, wherein the fuel injection system comprises a fuel pump and a plurality of injection valves, each connected to a cylinder of an internal combustion engine, wherein the fuel pump and/or the injection valves produce pressure waves that cause fuel pressure fluctuations, and wherein depending on a respective current demanded fuel quantity in the internal combustion engine the fuel injection quantity is reduced or increased by using at least one actuator to produce additional pressure waves in the fuel injection system that modify the fuel pressure fluctuations with at least temporary boosting of said fuel pressure fluctuations.

Abstract: An apparatus for controlling an air-fuel ratio of an internal-combustion engine includes an air-fuel ratio detector, a fluctuation signal generating device, an air-fuel ratio fluctuation device, a 0.5th-order frequency component strength calculator, a fluctuation frequency component strength calculator, a reference component strength calculator, and an imbalance fault determining device. The reference component strength calculator is configured to calculate strength of a reference component in accordance with strength of a first frequency component and strength of a second frequency component. The imbalance fault determining device is configured to make a determination of an imbalance fault in which air-fuel ratios of a plurality of cylinders vary beyond a tolerance limit on a basis of a relative relationship between strength of the 0.5th-order frequency component and the strength of the reference component.

Abstract: A control system for controlling a power output of a gas engine of the present invention includes a target value setting section for setting as a target value a restricted power output which is less than a predetermined power output when a source gas pressure of a gas fuel is less than a predetermined value required to inject the gas fuel against an intake-air pressure according to the predetermined power output, a power output setting section for setting a set value of a power output based on the target value set by the target value setting section, and a power output control section for controlling the power output so that the power output reaches the set value set by the power output setting section.

Abstract: A microcomputer determines, in a first monitoring routine, whether a required injection amount was normally computed in a fuel injection amount control routine, based on the required injection amount computed in the fuel injection amount control routine, and detected values of engine operating conditions used for computation of the required injection amount in the routine, and determines, in a second monitoring routine, whether an injector was normally driven based on the required injection amount, based on the required injection amount computed in the fuel injection amount control routine, and a measurement result of a current application period of injector drive current.

Abstract: A system includes a controller operable to control an engine in an operating mode. The controller operation is based at least in part on a first parameter set and on a second parameter set. The first parameter set is associated with an engine fuel supply and includes information regarding characteristics of a first fuel and a second fuel. The first fuel and second fuel are not the same type of fuel. The second parameter set is associated with one or more engine operation threshold values.

Abstract: A method of operating a dual fuel compression ignition engine includes controlling a liquid fuel pressure within the liquid fuel common rail toward a desired liquid fuel pressure, and controlling a gaseous fuel pressure within the gaseous fuel common rail toward a desired gaseous fuel pressure that is less than the desired liquid fuel pressure. The method also includes commanding a change in the liquid fuel pressure to a decreased liquid fuel pressure that is less than both the desired liquid fuel pressure and a current gaseous fuel pressure. The liquid fuel pressure is maintained above the gaseous fuel pressure during a transition of the liquid fuel pressure toward the decreased liquid fuel pressure by executing the pressure control algorithm.

Abstract: In an engine of a direct-injection type, a split injection (a fuel injection in an intake stroke and a fuel injection in a compression stroke) is carried out. A compression-stroke injection amount is gradually decreased or increased when the split injection is carried out. Engine rotational speed, which varies by combustion of such injected fuel, is detected for respective fuel injection amounts, which are varied (decreased or increased) as above. Such a fuel injection amount, with which the engine rotational speed becomes maximum, is calculated and set as a basic injection amount for the compression-stroke injection. The fuel injection in the compression stroke is then controlled based on the basic injection amount.

Abstract: Various approaches are described for air-fuel ratio control in an engine. In one example, a method include adjusting fuel injection from an anticipatory controller responsive to exhaust oxygen feedback of an exhaust gas sensor positioned upstream of an exhaust catalyst, the anticipatory controller including a first integral term and a second integral term, the second integral term correcting for past fuel disturbances. In this way, it is possible to provide fast responses to errors via the anticipatory controller, while corrected known past fueling errors, on average, via the second integral term.

Abstract: Large numbers of engine parameters result in a need for significant processing power to calculate the engine control values using algorithms in real-time. The disclosure provides an engine control system having a data library comprising an explicit model predictive control derived set of output data values. The data library comprises a subset of output data values in respect of each combination of input data values. The subset of output data values may be configured to control one or more aspects of engine performance.

Abstract: A navigation device apparatus and method are provided. The apparatus includes a fuel consumption determination unit that determines a fuel consumption during a travel of a vehicle. Also included is a fuel consumption information storage unit that stores point information identifying a departing point and a destination in the travel of the vehicle and fuel consumption information identifying the fuel consumption during a previous travel A display unit is included that acquires previous fuel consumption information identifying the fuel consumption during the previous travel corresponding to the departing point and the destination during a current travel of the vehicle, and controls the display of the fuel consumption during the previous travel based on the acquired previous fuel consumption information and the fuel consumption during the current travel determined by the fuel consumption determination unit.

Abstract: A hybrid vehicle is provided in which after a determination is made as to whether the remaining capacity is higher than a first threshold value, any one of a first running mode, a second running mode, and a third running mode is selected depending on first speed, second speed, or third speed so that the vehicle runs in the mode, whereby the vehicle can run by easily selecting an appropriate series hybrid mode or an appropriate parallel hybrid mode in each range depending on whether the remaining capacity is higher than the first threshold value, and running control can be made stable and easy.

Abstract: A method of controlling an amount of fuel to be injected by a fuel injector into a cylinder of an internal combustion engine is disclosed. A map stores values of a fuel injection quantity drift of said injector. A fuel injection quantity drift is estimated and stored in a corresponding map point to a current engine operating point. A set of map points whose distance from said corresponding map point is smaller than a given distance are selected. All map points of the set of map points are modified by multiplying their entries by a radial weighing factor. The amount of fuel to be injected by the fuel injector to be the requested amount of fuel is corrected by means of the corresponding entry of the map.

Abstract: A method of estimating an injection pressure for an internal combustion engine of an automotive system is disclosed that is well-suited for use with a digital pressure sensor, which periodically acquires injection pressure signals. An updated injection pressure value is calculated starting from an injection pressure signal and compensated with a pressure-correcting parameter, based on an elapsed time from the injection pressure signal acquisition, an actual engine speed and an actual fuel injection quantity.

Abstract: A fuel control system for a vehicle includes a pressure compensation module that compensates an intake oxygen signal based on an intake pressure signal and that generates a compensated intake oxygen signal. A blow-by estimation module generates an estimated blow-by flow. A purge flow estimation module estimates the purge flow based on the compensated intake oxygen signal and the estimated blow-by flow. A fuel control estimation module reduces fueling to injectors of an engine of the vehicle based on the purge flow.

Abstract: A system and method are described for reducing NOx emissions following deceleration fuel shut off (DFSO). The method comprises: cutting off fuel to the engine during a deceleration event; open loop operating the engine air/fuel ratio rich of stoichiometry for a predetermined time after the deceleration event; feedback controlling the air/fuel ratio on average near a value rich of stoichiometry for a preselected time after said predetermined time; and feedback controlling the air/fuel ratio returning to stoichiometry after the preselected time.

Abstract: A method and apparatus for controlling fuel injection in an internal combustion engine is disclosed which controls a fuel injection pressure and a fuel injection energizing time, by using as input parameter an estimated corrected injector fuel quantity (Qertd). In particular, an injector fuel quantity deviation (?QCB) corresponding to a current engine operating point is estimated and stored in a corresponding point of a map, representing engine operating points defined in terms of injection pressure and injector fuel quantity values. The stored injector fuel quantity deviation (?Qstored) are spread or propagated to each map point. For each engine operating point, the corrected injector fuel quantity (Qertd) is calculated by blending estimated values of the injector fuel quantity deviation (?QCB) with corresponding spread values of the stored injector fuel quantity deviation (?Qstored) and summing this result to corresponding target values of the injector fuel quantity (Qtarget).

Abstract: A fuel injection control device for an engine executes a split injection constructed by a fixed injection and a variable injection. A required injection amount of the fixed injection is set in a low range. A required injection amount of the variable injection is set in a high range. An injection amount in the high range is larger than that of the low range. The required injection amount of the variable injection is changed within the high range while the required injection amount of the fixed injection is fixed when a load of the engine is varied while the split injection is performed. An injection control characteristic is corrected based on an actual air-fuel ratio detected before the load is varied and an actual air-fuel ratio detected after the load is varied.

Abstract: Engines produce not only primary energy in the form of kinetic energy transmitted through a rotating crankshaft but also secondary energy which may comprise kinetic energy in other forms as well as thermal energy. In order to reduce engine running costs and increase efficiency there is a desire to make best use of all forms of energy produced by an engine. The disclosure relates to the adoption of an equivalent consumption minimisation strategy by which the engine may be controlled to derive useful energy from a first proportion of primary energy and a second proportion of secondary energy wherein the first and second proportions are selected to minimise overall energy consumption.

Abstract: Methods are provided for reducing transient fuel issues in a multi-fuel engine system. When transitioning from co-fueling with a first fuel split ratio to co-fueling with an alternate fuel split ratio, the change in fuel split ratio is gradually ramped in over multiple engine cycles. This reduces combustion stability issues and the disturbance potential of a wholesale fuel change.

Abstract: An electronic control unit, in an idle operating state, detects a crankshaft rotation fluctuation in each cylinder using a crank angle sensor, and updates an individual correction value for a control value for each fuel injection valve as a first learned value such that a degree of deviation in the crankshaft rotation fluctuation among the cylinders reduces. The electronic control unit uses a fuel pressure sensor to detect a manner of a fuel pressure fluctuation with fuel injection by each fuel injection valve, and updates an individual correction value for a control value for each fuel injection valve as a second learned value based on a result of comparison between a detected temporal waveform and a basic temporal waveform. In an idle operating state, a learning rate of the second learned value is reduced until the first learned value converges for the first time as compared with after its convergence.