Abstract: A control system and method for operating an engine includes a threshold determination module that determines a plurality of combustion mode thresholds based on the engine speed and engine temperature. The control module also includes a transition module that compares the engine load and the plurality of combustion mode thresholds and changes a combustion mode of the engine in response to comparing the engine load and the plurality of combustion mode thresholds.

Abstract: An engine control system for a homogeneous charge compression ignition (HCCI) engine includes a position determination module, a position correction module, and a valve control module. The position determination module determines an initial position of an exhaust gas recirculation (EGR) valve based on a predetermined function of a desired EGR flow, intake manifold pressure, exhaust manifold pressure, and exhaust gas temperature. The position correction module determines a position correction for the EGR valve based on pressure in a cylinder of the HCCI engine. The valve control module commands the EGR valve to the initial position during a transition from spark ignition (SI) combustion to HCCI combustion, and commands the EGR valve to a final position within a predetermined period after the transition, wherein the final position includes a sum of the initial position and the position correction.

Abstract: A system for controlling intake airflow of an engine includes a mode determination module, a throttle valve control module, and a valve actuation module. The mode determination module generates a mode signal based on an engine speed signal and an engine load signal. The mode signal indicates one of a spark ignition mode and a homogeneous charge compression ignition mode. The throttle valve control module generates a valve control signal based on the mode signal, a temperature signal, and a plurality of valve position signals that indicate positions of first and second throttle valves. The throttle valve control module controls the positions of the first and second throttle valves to regulate flow rates of intake air into an intake manifold of the engine via a heat exchanger based on the valve control signal. The valve actuation module actuates the first and second throttle valves based on the valve control signal.

Abstract: A method is disclosed for controlling cylinder valve switching between a first valve condition and a second valve condition for transitioning between combustion modes of an engine. The method includes adjusting timing of a signal to switch between the valve conditions based on an oil degradation condition from an oil sensor, wherein the combustion modes include spark ignition and homogenous charge compression ignition.

Abstract: A fuel injector body has a fuel chamber and a valve seat around a fuel outlet. A valve body is positioned at the valve seat and a valve stem extends through the fuel outlet and fuel chamber. Engagement (disengagement) of valve body and valve seat closes (opens) the injector. The fuel chamber can comprise primary and secondary chambers connected by a valve passage and a metering member that restricts fuel flow between the chambers, thereby providing a flow-dependent closing force that reduces the dependence of fuel flow through the injector on fuel inlet pressure and that makes that flow dependent on an injector actuating force. The injector body or the valve body can comprise a spray-shaping surface arranged at least partly around the valve seat, which spray-shaping surface is arranged to direct a spray of fuel flowing through the fuel outlet.

Abstract: An engine provided with a fuel injector for directly injecting fuel into a cylinder, a spark plug positioning a spark gap in a flight path of fuel injected from the fuel injector, and a cavity formed in a piston top face, wherein at the time of stratified combustion, the fuel injector injects substantially all of the fuel in a direction merging with a tumble flow, swirling in a longitudinal direction along the cavity at the compression stroke, along the swirl direction of the tumble flow and uses the spark plug to ignite the fuel while the fuel at the end period of injection is passing through the spark gap.

Abstract: An engine control system for a homogenous charge compression ignition (HCCI) engine includes a fuel injector temperature determination module and a fuel injector control module. The fuel injector temperature determination module determines a temperature of a tip of a fuel injector based on a first temperature model when the HCCI engine is operating in an HCCI combustion mode, and determines the temperature of the tip of the fuel injector based on a second temperature model when the HCCI engine is operating in a spark ignition (SI) combustion mode. The fuel injector control module controls a fuel injector pulse width based on the determined temperature and a predetermined temperature threshold, wherein the fuel injector pulse width increases when the determined temperature is greater than the predetermined temperature threshold.

Abstract: A combustion timing prediction method for a compression self-ignition internal combustion engine includes the steps of: specifying types of a plurality of hydrocarbon components contained in a hydrocarbon fuel and proportions of the respective types in the hydrocarbon fuel; calculating, on the basis of a temperature in a combustion chamber of the internal combustion engine, a value of a first function serving as a function of the temperature for each of the types; calculating, on the basis of the proportion and the first function relating to each of the types, a value of a second function, which is a function that increases in value in response to an increase of the value of the first function and/or the proportion, for each of the types; integrating the values of the second function relating to the respective types; and predicting, on the basis of the integrated value of the values of the second function, the combustion timing of the hydrocarbon fuel in the internal combustion engine to be steadily later as

Abstract: In a method for changing the operating mode in an internal combustion engine it is possible to switch between an operating mode with spark ignition of the engine and an operating mode with auto-ignition of the engine. Hereby, a first map is provided in which at least one range is specified in which a suitable auto-ignition of the engine can take place. After the engine start, therefore, it is determined whether the engine has reached an operating point lying within this range of the first map in order then to switch the engine to the operating mode in which auto-ignition can take place reliably.

Abstract: A method for transitioning operation of a spark-ignition, direct-injection internal combustion engine having a two-step, variable phase valvetrain between HCCI and SI modes includes providing a low-lift intake valve, un-throttled stoichiometric SI operation intermediate a low-lift exhaust and intake valve HCCI mode and a high-lift exhaust and intake valve, un-throttled SI mode.

Abstract: In a method for starting a self-igniting internal combustion engine at low temperatures, a first fuel amount is injected into the combustion chamber during a compression stroke of the internal combustion engine by a fuel pre-injection, so as to form a partially homogenous pre-mixture in the combustion chamber; a main fuel amount is then injected into the combustion chamber during a main injection and the fuel/air mixture is combusted by self-ignition, the injection start of the pre-injection being selected such that the partially homogenous pre-mixture can be ignited after a very short ignition delay, and an injection start of the main injection is selected such that the main fuel amount is injected into the combustion chamber either during a combustion phase or directly after a combustion phase of the ignited pre-injection mixture

Abstract: In order to operate an internal combustion engine, a fresh-air quantity, a residual-gas quantity and a fuel quantity are provided as a function of a load demand. During a change of load from a first to a second load demand, provision is made for the residual-gas quantity to first be provided according to the first load demand and for the fuel quantity to first be provided according to the second load demand.

Abstract: A method for operating an internal combustion engine including extended operation in a homogeneous charge compression ignition mode at high loads includes operating the engine in the homogeneous charge compression ignition mode including spark-assisted ignition, monitoring an engine load, monitoring an engine speed, determining the engine to be in a high ringing range based upon the engine load and the engine speed, and when the engine load is in the high ringing range, operating the engine in a reduced ringing mode. The reduced ringing mode includes modulating a fuel injection timing according to a calibrated maximum combustion chamber cooling fuel injection timing, determining a preferred combustion phasing value, and modulating a spark timing based upon the modulated fuel injection timing and the preferred combustion phasing value.

Abstract: In a direct injection spark ignition internal combustion engine that includes a fuel injection valve, and closes an intake valve after gas in the combustion chamber begins to flow back into an intake passageway after the compression stroke begins. The required fuel injection amount is injected a first fuel injection event and a second fuel injection event in a single combustion cycle, and the first fuel injection is performed while the intake valve is open during the compression stroke, and the second fuel injection is performed after the intake valve closes. The timing of the first fuel injection event is set such that the injected fuel is deflected upwards in the top of the combustion chamber by the gas flowing toward the intake valve.

Abstract: An intake air control apparatus comprises an intake air path connected to a combustion chamber, and an intake airflow control device having a first opening deviated in one direction when viewed from an axial direction of the intake air path by partially closing a cross-section of a flow path of the intake air path, and that controls distribution of an intake airflow by deviating the intake airflow downstream of the first opening to a side in which the first opening is formed, the intake airflow control device having a second opening of smaller opening area than that of the first opening, and deviated in an opposite side to the side in which the first opening is formed and at a location away from an intake air path wall.

Abstract: A fuel for a homogeneous charge compression ignition engine having a 95 V % distilled temperature by boiling point measurement in the range of about 35.degree. C. to about 350.degree. C., a cetane number in the range of about 2 to about 120, and an octane number in the range of 10 to about 110. The invention also relates to a method of operating a homogeneous charge compression ignition engine of mixing a fuel with air and feeding the fuel into a combustion chamber.

Abstract: Fuel management system for efficient operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder of the engine. A fuel management microprocessor system controls injection of the anti-knock agent so as to control knock and minimize that amount of the anti-knock agent that is used in a drive cycle. It is preferred that the anti-knock agent is ethanol. The use of ethanol can be further minimized by injection in a non-uniform manner within a cylinder. The ethanol injection suppresses knock so that higher compression ratio and/or engine downsizing from increased turbocharging or supercharging can be used to increase the efficiency of the engine.

Abstract: An internal combustion engine includes a fuel system having a first fuel rail with an integrated diverter portion coupled to a high-pressure pump and separated from a common rail portion by a flow restriction device. The first fuel rail includes a pressure sensor coupled to the diverter portion at one end and a control valve coupled to the common rail portion at the other end of the same fuel rail. In V-engine embodiments, a second fuel rail communicates with the integrated diverter portion of the first fuel rail. In one embodiment, components including the first and second fuel rails, a pressure sensor, and a pressure or volume control valve are externally mounted outside the engine valve cover.

Abstract: A method and system for controlling an engine includes a homogenous charge compression ignition (HCCI) mode control module that operates an engine in HCCI mode and a condition monitor module that monitors operating conditions of the engine. The control module also includes a condition predictor module that generates a first predicted condition of a catalyst in response to the operating conditions of the engine. A comparison module compares the first predicted condition to a first threshold. A spark injection mode control module operates the engine in a spark injection mode in response to comparing.

Abstract: An HCCI engine provides a negative overlap period in an operation during HCCI combustion. During the negative overlap period, an intake valve and an exhaust valve are both closed when a piston is in the vicinity of the top dead center in an exhaust stroke, so that burned gas remains inside a combustion chamber. The engine is provided with a throttle, a fuel valve and an ECU. The ECU controls the throttle during a switching period in which SI combustion is switched to the HCCI combustion so that the opening degree of the throttle increases to the opening degree at the time of steady HCCI operation from the opening degree at the time of steady SI operation, and at the same time, controls the fuel valve such that the amount of fuel supplied to the intake passage becomes greater than the amount at the time of the steady SI operation.

Abstract: A method for controlling the start of combustion and peak burn rate of an internal combustion engine system on a cycle-to-cycle basis including multiple direct fuel injectors, multiple indirect fuel injectors, and multiple liquid fuels. The actual start of combustion and actual peak burn rate are calculated using in-cylinder pressure or ionization. A predetermined start of combustion and a predetermined peak burn rate are selected. The start of combustion and peak burn rate control algorithm includes controlling a fuel ratio, an injection ratio, and a residual gas recirculation ratio. A predetermined fuel ratio, a predetermined injection ratio, and a predetermined residual gas recirculation are calculated by combining feed forward ratios and closed loop control ratios corresponding to the three ratios. The predetermined ratios are employed so that the system achieves the predetermined start of combustion and predetermined peak burn rate.

Abstract: A method of controlling fuel supplied to an engine is provided. The engine includes at least one cylinder having a port injection fuel injector being supplied with fuel from at least one of a first fuel storage tank and a second fuel storage tank and a direct injection fuel injector being selectively supplied with fuel from one of the first fuel storage tank and the second fuel storage tank. The method includes at a first condition, supplying at least some of a second type of fuel from the second fuel storage tank to the direct injection fuel injector and supplying at least some of a first type of fuel from the first fuel storage tank to the port injection fuel injector, and at a second condition, supplying at least some of the first type of fuel from the first fuel storage tank to the direct injection fuel injector.

Abstract: A variable displacement engine comprises two engine modules fed from a common fuel source, each engine module having an individual crankshaft. The first engine module has a high compression ratio (e.g., greater than 13:1), while the second module has a typical compression ratio for a gasoline engine (e.g., between 9:1 and 11:1). In one embodiment, the first engine module operates through high efficiency optimized alcohol fuel combustion when the fuel content exceeds a minimum alcohol content. In an alternative embodiment, the first engine module operates at high efficiency through gasoline HCCI combustion when conditions permit. When operating conditions do not permit the first engine module to operate at high efficiency, the second engine module operates as the primary engine module, with the first engine module available to provide supplemental power (at less than optimal efficiency) if needed to meet driver demand.

Abstract: A method of transitioning between operating modes in a multimode engine including a diesel-only mode and a diesel pilot, gas mode includes first terminating or initiating the supply of a gaseous fuel, depending on whether the system is transitioning to or from the pilot mode, and thereafter decreasing or increasing the diesel fuel supply quantity. Liquid fuel supply quantity is preferably altered in steps rather than discretely in order to avoid exceeding the lean limit of gas lambda. The number of steps and the percentage decrease or increase in each step preferably varies based at least in part on prevailing speed and load conditions.

Abstract: An engine mode control system for an internal combustion engine includes a transition control module and an intake cam phaser control module. The transition control module controls a transition from a first engine mode to a second engine mode and determines a desired air mass. The engine is operated at a first air/fuel ratio (AFR) in the first engine mode and at a second AFR in the second engine mode. The desired air mass is based on the second AFR. The intake cam phaser control module adjusts the intake cam phaser based on the desired air mass during the transition.

Abstract: A multifuel internal combustion engine includes: fuel characteristics determining unit that determines ignitability and anti-knocking performance of the fuel introduced into the combustion chamber CC; combustion mode setting unit that sets a compression hypergolic diffusion combustion mode when ignitability of the fuel is excellent, sets a premixed spark-ignition flame propagation combustion mode when the ignitability of the fuel is poor and anti-knocking performance is excellent, and sets a spark assist compression hypergolic diffusion combustion mode when both the ignitability and anti-knocking performance of the fuel are poor; and combustion control execution unit that makes the engine to drive in a combustion mode which is set by the combustion mode setting unit.

Abstract: A fuel for a homogeneous charge compression ignition engine having a 95 V % distilled temperature by boiling point measurement in the range of about 35.degree. C. to about 350.degree. C., a cetane number in the range of about 2 to about 120, and an octane number in the range of 10 to about 110. The invention also relates to a method of operating a homogeneous charge compression ignition engine of mixing a fuel with air and feeding the fuel into a combustion chamber.

Abstract: When it is determined that an engine operating condition is in a high-engine load HCCI range (A2) where an engine load is higher than a specified load X1 within a HCCI range A where a compression self combustion is performed, an after-TDC injection F2s is executed at a point T1 when an internal pressure of a combustion chamber drops below a specified pressure Y after the top dead center of an exhaust stroke during a minus valve overlap period NVO during which intake and exhaust valves are both closed. Then, a main injection F2m as a main injection is executed. Accordingly, any improper detonation or deterioration of NOx emission which may be caused by the compression self-ignition combustion in the range where the engine load is relatively high can be prevented.

Abstract: A controller of an internal combustion engine capable of spark ignition combustion and compression ignition combustion which restrains the degradation of operation performance and exhaust performance at the time of combustion type switching. The controller includes control means for performing combined combustion which leads to ignition combustion by a pressure rise by spark ignition combustion through adjustment of an internal cylinder temperature and a combustion speed at the end of compression, wherein the combined combustion is performed in the process of combustion type switching between spark ignition combustion and compression ignition combustion based on a result of determination of whether or not combustion type switching is possible, thus implementing a smooth combustion type switching.

Abstract: A method is provided for operating a lean-burn homogeneous charge reciprocating internal combustion engine that includes providing an unthrottled fuel-air compression charge having a lean fuel-air ratio, passing the fuel-air compression charge to fill no more than sixty percent of a cylinder within the internal combustion engine, compressing the fuel-air compression charge within the cylinder, igniting the compressed fuel-air compression charge for combustion, and passing exhaust resulting from the combustion to a NOx removal system. A non-platinum oxidation catalyst may be used to control carbon monoxide emissions in the exhaust Engine power may be varied by controlling the engine speed with a continuously variable transmission, by varying the applied engine load to charge a hybrid system battery, or by varying the amount of the lean fuel-air mixture charged.

Abstract: A method is provided for achieving low NOx operation of homogeneous charge, lean burn reciprocating internal combustion engines. The method incorporates providing a fuel-air compression charge having a lean fuel-air ratio of less than the lean flammable limit, compressing the fuel-air compression charge to raise the adiabatic flame temperature to a predetermined value above the lean flammable limit, and igniting the compressed charge for combustion. A non-platinum oxidation catalyst may be included to control carbon monoxide emissions in the exhaust.

Abstract: The Internal-Combustion Engine is set forth, in which when in use there is no lateral component of the force on the piston which is taken up by the slider rolling by the bearings. As a result of this the cylinder compression is improved, power losses on friction are reduced and wear out of the cylinder is decreased. Also due to the absence of the lateral component of the force on the piston, the latter can be made in a relieved version, e.g. without a skirt and with two compressing rings in one groove.

Abstract: A control system and method for operating an engine includes an HCCI mode control module operating an engine in a homogeneous charge compression (HCCI) mode. The control system also includes a difference module determining an actual difference between a desired torque amount and a spark ignition (SI) threshold. An SI mode control module operates the engine in a SI state when the actual difference is above a threshold band. A HCCI mode control module operates the engine in the HCCI mode for a predetermined time when the actual difference is within the torque threshold band. The HCCI mode control module operates the engine in the HCCI mode when the actual difference is below the torque threshold band.

Abstract: The present disclosure provides an internal combustion engine having an engine housing with at least one cylinder that has diameter less than about 3 inches. A fuel injector is provided and disposed at least partially within the at least one cylinder, and includes a plurality of outlet orifices having a diameter between about 50 microns and about 125 microns, or about 0.05 millimeters and about 0.125 millimeters. The injector may include more than one set of separately controllable fuel outlet orifices, at least one of which could have an average diameter between about 0.05 millimeters and about 0.125 millimeters. The disclosure further provides a method of operating an internal combustion engine.

Abstract: A control system and method for operating an engine includes a transition module that commands engine control from a first homogeneous charge compression (HCCI) mode to a second HCCI mode. The control system also includes a fuel delivery module that operates the engine in a stratified charge operation mode after commanding engine control from the first HCCI mode to the second HCCI mode and discontinues the stratified charge operation thereafter.

Abstract: In a premixed compression ignition diesel engine 1 with fuel being injected midway of a intake passage 15, an intake port 6 is formed with an orifice 10 which is throttled in passage cross-sectional area at least in an opening operation of an intake valve 7. This prevents adhesion of the fuel to an inner wall of the intake passage and promotes atomization of the fuel. A combustion chamber is fed with the sufficiently atomized fuel, which prevents combustion failure in the combustion chamber to attain reduction of particulate matters.

Abstract: An HCCI engine operated in HCCI and SI combustion modes. The engine includes an external EGR apparatus for performing external EGR. A control unit executes combustion control by specifying either one of HCCI and SI combustion ranges based on the driving state of the engine and a combustion range map for specifying the combustion range in accordance with the driving state. The map includes the HCCI and SI combustion ranges and a switch preparation combustion range, which is included in the SI combustion range and extends along a boundary between the SI combustion range and the HCCI combustion range. The control unit lowers the temperature in the combustion chamber when the switch preparation combustion range is specified by reducing the amount of internal EGR or performing the external EGR.

Abstract: In an engine 5 including an in-cylinder injector, the valve timing of an intake valve is retarded by VVT (Variable Valve Timing) controlled by an engine ECU to decompress in a combustion chamber at engine startup. In accordance with a configuration in which the valve timing of intake valve is advanced in a stepped manner from an initial set value, fuel injection from in-cylinder injector is inhibited during the time when the advance is equal to or below a predetermined standard value, and fuel injection from in-cylinder injector is allowed when exceeding the predetermined standard value, whereby degradation in the exhaust emission level in accordance with start time decompression control can be suppressed.

Abstract: The invention relates to an internal combustion engine operable in homogeneous charge compression ignition (HCCI) combustion mode and in conventional spark ignited combustion mode and a method for restart of HCCI combustion therein. Whilst cranking the exhaust valve is arranged to be closed before top dead center (TDC) during an exhaust stroke. The intake valve is arranged to be opened after TDC during an induction stroke. Fuel injection control means are arranged to perform a first fuel injection after closing of the exhaust valve and before TDC of the exhaust stroke. The ignition control means are arranged to cause said spark plug to ignite the first injected quantity of fuel before said opening of the intake valve. The fuel injection control means are arranged to perform at least one further fuel injection in the interval after TDC of the exhaust stroke and before TDC of a subsequent compression stroke.

Abstract: An engine operating in a spark-assisted homogeneous charge compression ignition mode during warm-up cycle is controlled using settings determined by interpolating between cold engine temperature settings fully warmed-up engine temperature settings.

Abstract: A method for controlling regeneration of a lean NOx trap includes estimating an accumulated NOx in the lean NOx trap; determining whether the estimated NOx exceeds a first threshold value or a second threshold value; estimating the temperature of the lean NOx trap; determining whether the estimated temperature exceeds a threshold temperature; determining a desired air-fuel ratio for initiating a regeneration event, the desired air-fuel ratio being determined based upon the estimated NOx and the estimated temperature of the lean NOx trap; hastening the occurrence of a regeneration event when the estimated NOx exceeds the first threshold value through active control of engine operating regimes; and initiating a regeneration event when the estimated NOx exceeds the second threshold value or when the estimated temperature exceeds the threshold temperature by forcing homogenous operation of the engine at the desired air-fuel ratio.

Abstract: An HCCI engine capable of switching combustion mode between SI combustion and HCCI combustion is disclosed. At least one swirl port and at least one tumble port communicate with a combustion chamber of the HCCI engine. In a first switching period in which the SI combustion is switched to the HCCI combustion, intake air is supplied to the combustion chamber solely through the swirl port. In a second switching period in which the HCCI combustion is switched to the SI combustion, the intake air is supplied to the combustion chamber through at least the tumble port.

Abstract: A compression-ignition internal combustion engine system having an exhaust passage and an exhaust gas treatment arrangement, wherein the exhaust gas treatment arrangement comprises a three-way catalytic converter.

Abstract: A method for operating an internal combustion engine including extended operation in a homogeneous charge compression ignition mode at high loads includes operating the engine in the homogeneous charge compression ignition mode including spark-assisted ignition, monitoring an engine load, monitoring an engine speed, determining the engine to be in a high ringing range based upon the engine load and the engine speed, and when the engine load is in the high ringing range, operating the engine in a reduced ringing mode. The reduced ringing mode includes modulating a fuel injection timing according to a calibrated maximum combustion chamber cooling fuel injection timing, determining a preferred combustion phasing value, and modulating a spark timing based upon the modulated fuel injection timing and the preferred combustion phasing value.

Abstract: A method for controlling an internal combustion engine having a common rail system together with individual accumulators. A rotational speed-control deviation (dn) is determined from a target rotational speed (nSL) that represents the set point for an outer control loop to control the rotational speed, as well as from an actual rotational speed (nIST). A target torque (MSL) is determined from the rotational speed-control deviation (dn) via a rotational speed controller as a master controller. A target injection duration (SD(SOLL)) is determined from the target torque (MSL). The target duration injection (SD(SOLL)) represents the set point for an inner control loop for controlling cylinder-specific injection duration. An injection duration deviation is determined from the target injection duration (SD(SOLL)) and from an actual injection duration.

Abstract: A method for operating an internal combustion engine in a state of controlled self-ignition. The internal combustion engine includes a combustion chamber, at least one intake valve and at least one exhaust valve whose opening times can be changed. A fresh mixture is introduced into the combustion chamber during an intake stroke and an ignitable gas mixture is produced in the combustion chamber by way of the introduction of fuel and compressed in a compression stroke, whereby the gas mixture self-ignites toward the end of the compression stroke.The fresh mixture is introduced into the combustion chamber by way of a compression mechanism during the intake stroke.

Abstract: A HCCI engine (1) is able to supply two types of fuels with different octane numbers to each cylinder (3) through fuel supply devices (17 and 18). A fuel supply control means (50) of a controller (2) increases a proportion of a supplied quantity of a low-octane fuel in the entire supplied quantity of the respective two types of fuels to a combustion chamber greater than a normal proportion defined by a normal control operation value group determined by a predefined control rule according to a FC correction processor (57) in a predefined duration immediately after a return of a working mode from a fuel-cut mode to a normal mode. Thereby, it is able to efficiently perform combustion of the fuel-air mixture in the combustion chamber even after the return of the working mode from the fuel-cut mode to the normal mode when a temperature in the combustion chamber is low.

Abstract: An engine has cylinders respectively connected to branch pipes branched from a main pipe as an intake manifold. Fuel injection valves are attached to branch pipes, respectively. Further, branch pipes are connected to branch pipes branched from an EGR pipe on a downstream side of EGR valve, and exhaust gas introduced from EGR valve is fed to each of branch pipes. ECU detects imbalance of air-fuel ratio among cylinders, based on cylinder-by-cylinder air-fuel ratio detected by air-fuel ratio sensors provided on branch pipes as an exhaust manifold. If there is an imbalance in air-fuel ratio among cylinders, EGR valve is closed and imbalance in air-fuel ratio among cylinders is again detected.

Abstract: A method is provided for controlling an engine via an outlet control device of an intake manifold, such as via variable valve lift operation. The engine may further include an inlet control device, such as an electronic throttle, as well as coordination between the inlet and outlet control devices for controlling airflow in the engine.

Abstract: An internal combustion engine system comprises: a dehydrogenation reactor which performs a dehydrogenation reaction to separate organic hydride-contained fuel into hydrogen and dehydrogenated fuel; supply means which supplies separated hydrogen and dehydrogenated fuel individually to the internal combustion engine; and control means which switches the operation of the internal combustion engine between a first mode in which both hydrogen and dehydrogenated fuel are supplied to the internal combustion engine and a second mode in which only hydrogen is supplied to the internal combustion engine.