Abstract: A number of systems and methods are disclosed which increase the replenishment interval for anti-knock fluid. This is especially important during activities which require a large amount of anti-knock fluid, such as towing. In some embodiments, the systems and methods are used to reduce anti-knock fluid consumption. For example, changes to engine operation, such as rich operation, spark retarding, upspeeding, and variable valve timing, all serve to reduce the amount of anti-knock fluid required to eliminate knocking. In other embodiments, the composition of the anti-knock fluid is modified, such as by using a higher octane fluid, or through the addition of water to the anti-knock fluid. In other embodiments, the replenishment interval is increased through a larger anti-knock fluid storage capacity. In one embodiment, a three tank system is used where the third tank can be used to store gasoline or anti-knock fluid, depending on the driving conditions.

Abstract: A process and apparatus is provided for burning liquid ammonia in an energy device such as a diesel engine, boiler or gas turbine. In particular, the process and apparatus include mixing a renewable fuel with a low flame speed and high ignition temperature, e.g., ammonia, with a combustible liquid fossil or bio-fuel and supplying the mixture into a closed fuel loop where part is efficiently burned in an engine combustion chamber, and part is used to cool the engine and returned by the loop for mixture with fresh incoming fuel mixture. The invention provides for the mixing and emulsifying in such a way that vapor lock is avoided. In the loop, the mixture is emulsified into a disperse distribution of fuel droplets such that upon injection of a portion into the combustion chamber, the renewable fuel in an emulsified droplet evaporates, mixes with the air and forms a small combustion cell surrounding the liquid fuel droplet.

Abstract: The present invention relates to a system and method for providing fuel to internal combustion engines including fuel activation prior to injection. The method carried out by the system comprises dissolving a mixture of gasses providing improved fuel dispersing after fuel injection into a combustion chamber. Dissolved gasses desorption is stimulated from a unsaturated fuel solution. Full control of fuel flows with dissolved gas/gasses to and from injectors and FET technology based on Henry's law (dissolving gasses in the liquids) and Kelvin principle (vapor pressure over droplet surface). The system consists of compact components, including exhaust gasses recirculation system which can be easily added to existing diesel and gasoline engine fuel supply systems. The method and system were tested with four different types of engines and provides fuel economy in 12-20% decrease of emissions and up to 25% at variable engine loads and significantly at engine cold start.

Abstract: A diesel engine for combusting a diesel-LPG mixture includes a fuel system for supplying diesel and LPG. The mixture is obtained by combining the fuel flow from a LPG tank and diesel tank. Increased pressure is applied in both fuel flows for mixing purposes. Immediately following the mixing a circulation system is present in which increase in pressure also takes place, wherein a part of the mixture is supplied to a high-pressure pump for injection to the diesel engine and a part is recirculated. In a method of supplying the diesel-LPG mixture, the part of the mixture that is supplied to the high-pressure pump is returned to a position upstream of the mixing point. The pressure in the fuel system is higher downstream of the mixing point. When the LPG supply is switched off the pressure can be gradually decreased through circulation.

Abstract: An ammonia burning internal combustion engine can feed ammonia and a highly combustible substance burning easier than ammonia to a combustion chamber. When the amount of ammonia fed into the combustion chamber is increased or when the ratio of the amount of the ammonia to the total amount of the ammonia and the highly combustible substance fed into the combustion chamber is increased, the operating parameters of the internal combustion engine are controlled so the air-fuel mixture fed into the combustion chamber is made easier to burn. As a result, an ammonia burning internal combustion engine designed to suppress a drop in combustibility of auxiliary fuel due to ammonia, can be provided.

Abstract: Methods and systems are provided for fuel systems including a gaseous fuel. Temporary flow restrictions in the fuel line of a first gaseous fuel may be addressed by temporarily shifting to cylinder operation with a second liquid fuel. Upon resumption of first fuel operation, if the flow restriction persists, a diagnostic code may be set and cylinder operation with the second fuel may be restarted.

Abstract: A fuel control system for controlling the purging of alternate fuel in an internal combustion engine at shutdown includes: at least one valve device configured to deliver a fuel supply to the engine; a first fuel source configured to provide a primary fuel to the valve device; a second fuel source configured to provide an alternate fuel to the valve device; and a controller connected to the valve device and adapted to be connected to an ignition system. The controller is configured to control the valve device responsive to a status of one of the engine and the ignition system.

Abstract: An engine system for determining an alcohol concentration in fuel is disclosed. In one example, engine throttle position, fuel pulse width, and air-fuel ratio form a basis for determining alcohol concentration of a fuel combusted in an engine. The system and its related method may improve engine operation in conjunction with detecting an alcohol concentration of a fuel.

Abstract: If the pressure in a supply passage drops at a speed greater than a first determination speed in a state in which a first mode for supplying gas fuel to an internal combustion engine is selected, a control apparatus inhibits selection of the first mode. Then, the control apparatus switches from the first mode to a second mode, in energy other than gas fuel is used. In this state, if the pressure in the supply passage drops at a speed greater than a second determination speed, the control apparatus maintains the state in which the second mode is selected. If the pressure in the supply passage drops at a speed lower than the second determination speed, the control apparatus cancels the inhibition of selection of the first mode when it is detected that a manual on-off valve is opened.

Abstract: A method for operating a condensed natural gas engine, comprising injecting a mass of additive into the engine, the mass of additive a function of a mass-of-soot desired and producing a mass-of-soot during combustion, mass-of-soot produced a function of the mass of additive injected into the engine. By this method additional soot may be produced for heightened lubrication and valve protection.

Abstract: A system and attendant structural components for incorporating an alternate fuel supply, such as of the type used in combination with a conventional distillate fuel, to power a heavy duty industrial vehicle, such as a mine haul dump truck. The system and attendant structure includes a mounting assembly structured for containment and support of the alternate fuel and a containment area disposed on the vehicle and structured and dimensioned to retain the mounting assembly therein. The containment area and the mounting assembly are disposed in laterally adjacent, exposed relation to an operator area of the mine haul truck, wherein the mounting assembly and the containment area are cooperatively disposed and structured to facilitate storage of the alternate fuel and operative communication and distribution thereof with the powering engine of the mine haul vehicle.

Abstract: A process for operating an internal combustion engine or a nozzle includes producing a fuel mixture in-situ. The fuel mixture consists of a polar component A, a nonpolar fuel component B, an amphiphilic component C, and an auxiliary component D. The fuel mixture is produced in a high-pressure region of an injection system of an internal combustion engine or of a nozzle within 10 seconds of an injection operation. The fuel mixture is injected into the internal combustion engine or the nozzle. A pressure is in a range of from 100 to 4,000 bar.

Abstract: An internal combustion engine includes a cylinder with a combustion chamber and a piston selectively changing the volume of the combustion chamber. The combustion chamber receives a mixture of air, hydrogen and a liquid fuel consisting essentially of water and a flammable, preferably non-fossil, substance. The contents of the combustion chamber are ignited generating power.

Abstract: The present invention relates to a method of controlling the combustion phase of a fuel mixture of a spark-ignition supercharged internal-combustion engine comprising at least one cylinder (12) with a combustion chamber (14), at least one fuel supply means (48, 52) and spark ignition means (38).

Abstract: Apparatus and methods for providing natural gas possessing at least one desired quality to at least one engine include providing raw natural gas and methane gas through first and second conduits, respectively. Based upon measurements of the desired quality or qualities of the raw natural gas, the electronic controller selectively varies the flow of methane gas to provide a blend of raw natural gas and methane gas that possesses desired quality or qualities to the engine(s).

Abstract: The present disclosure is directed at the control of an effective compression ratio setting in an engine which may use a variety of fuels or fuel blends. The effective compression ratio may be selected based upon information from a fuel sensor and stored information regarding the detected fuel composition. The effective compression ratio may be adjusted for a selected cylinder by intake or exhaust valve timing.

Abstract: A system, comprising, a combustion chamber, and a free-radical ignition system configured to inject free radicals into the combustion chamber at an ignition timing to trigger combustion of a fuel-air mixture.

Abstract: A compression ignition dual fuel engine utilizes individual fuel injectors to inject both gaseous and liquid fuels into each engine cylinder. Each of the fuel injectors includes two electrical actuators that control pressure in a respective liquid control chamber and gaseous control chamber to control the opening movement of check valves to facilitate liquid and gaseous fuel injection events, respectfully. The control fluid for liquid injection events is liquid, whereas the control fluid for the gaseous injection event is gaseous. The used liquid fuel drained from each fuel injector is returned for recirculation and subsequent injection, whereas the used gaseous fuel that drains from the fuel injector is supplied to the intake manifold for burning as circumstances permit.

Abstract: A fuel supply system of an internal combustion engine includes: a pressure adjustment device provided on a fuel flow path that connects a fuel pump and an injector; a return flow path for returning a fuel discharged from the pressure adjustment device to a fuel tank; a fuel property sensor disposed in the return flow path; a fuel pump control portion that actuates the fuel pump at a predetermined programmed timing, when the internal combustion engine is in a stopped state; and a fuel property determination portion that determines a fuel property of the fuel in the fuel tank by using an output value of the fuel property sensor, when the fuel pump is actuated during the stopped state of the internal combustion engine.

Abstract: Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

Abstract: A fuel control system and method for providing fuel to an internal combustion engine are provided. The fuel control system generally includes at least one valve device structured to deliver a fuel supply to the engine, a first fuel source structured to provide a primary fuel to the valve device, a second fuel source structured to provide an alternate fuel to the valve device, and an electronic controller structured to control the valve device. The electronic controller controls the valve device as a function of various data to selectively deliver the primary fuel and the alternate fuel to generate a fuel supply, e.g. as a mixture of the two fuels. The data used to control the fuel supply may include GPS data, engine data, environmental data, and/or other operational data.

Abstract: A twin vertical bank hybrid internal combustion H-engine system; an assembly having an engine block with parallel left side and right side vertical inline piston banks, each having a crankshaft and pistons, a cylinder head, and individual fuel feeds operable on a first and second fuel type respectively. Each piston bank operates independently of the other but is housed within the same engine block and has separate lubrication systems. An operator selects which engine to run based on fuel availability, convenience, or lower cost of a certain fuel type. The chosen engine is mechanically or electrically selected via an engine bank selector box using a selector control which selects the fuel type and engages a drive gear on the crankshaft of the selected engine, and transfers power to the transmission. The selector control actuates a transfer system that prevents simultaneous operation of both engines.

Abstract: The present invention provides a control apparatus used in an internal combustion engine that can switchably use a compressed natural gas and gasoline. The control apparatus carries out a miss fire check on the internal combustion engine over two or more combustion cycles, and, based on the results of the check, detects failures. The control apparatus prohibits switching of fuels (S23, S24, S28) basically during the miss fire check. If the value of a miss fire counter is not increasing, the control apparatus predicts that a negative check result will not be obtained (S26), and lifts the prohibition on switching of fuels (S29).

Abstract: A dual fuel injection valve with concentric needles comprises an inner needle and an outer needle surrounding the inner needle, both needles being located inside the injection valve body. The valve is provided with a first set and a second set of orifices for separately injecting two different fuels directly into the combustion chamber of an internal combustion engine. The outer needle is fixed against rotation with respect to the injection valve body such that an interlace angle between the centerlines of the first series of orifices and second series of orifices is set at different predetermined angles to reduce methane emissions.

Abstract: In a fuel injection system of an internal combustion engine in which a first fuel, which has a property to inhibit the adsorption of exhaust gas components by an exhaust gas purification catalyst, and the second fuel, which has a property not to inhibit the adsorption of the exhaust gas components by the exhaust gas purification catalyst, are able to be selectively used, the present invention has a task to decrease an amount of consumption of the second fuel in a suitable manner. In order to solve this task, the fuel injection system of an internal combustion engine according the present invention is constructed such that the second fuel is first supplied to the internal combustion engine when the exhaust gas purification catalyst is in a cold state, and a change from the second fuel to the first fuel is then made before the exhaust gas purification catalyst subsequently rises in temperature to an activation temperature thereof.

Abstract: An engine includes a fuel tank with a fuel tank body defining an internal fuel tank volume for containing a fuel, a vent conduit integrally formed with the fuel tank body, and an air cleaner system including an air cleaner housing defining an internal air cleaner volume. The vent conduit extends between an inlet aperture and an outlet aperture. The inlet aperture is in fluid communication with the internal fuel tank volume. An opening is formed in the air cleaner housing and the vent conduit extends through the opening. The outlet aperture of the vent conduit is positioned within the internal air cleaner volume and the vent conduit provides fluid communication between the internal fuel tank volume and the internal air cleaner volume.

Abstract: A gaseous fuel internal combustion engine includes an engine housing defining at least one cylinder, and an intake housing defining an intake passage fluidly connecting with the at least one cylinder. The engine includes a gaseous fuel delivery mechanism coupled with the engine housing and a distributed ignition promoting mechanism having a bead presentation device extending into the intake passage and configured to present a liquid bead of distributed ignition promoting material therein such as engine lubricating oil. During operation, gases passing through the intake passage dislodge the liquid bead from the bead presentation device and carry the distributed ignition promoting material into the cylinder for distributively igniting therein a mixture containing a gaseous fuel, air and the distributed ignition promoting material.

Abstract: A fuel injection apparatus includes: an adsorbent disposed in an internal space of a leading end portion of a fuel injector, the adsorbent being capable of selectively adsorbing an alcohol component in the blended fuel of gasoline and alcohol; fuel pressure controller capable of achieving states in which a pressure of fuel to be supplied to the fuel injector is set to a low or high pressure range having a small or large adsorbed amount of alcohol on the adsorbent; and split injection controller that makes the fuel injector inject fuel for one cycle in a plurality of times, when the pressure of fuel to be supplied to the fuel injector is set to the high pressure range.

Abstract: A spark ignition internal combustion engine is equipped with a fuel pressure sensor for detecting a viscosity of fuel supplied to a fuel injector based on a variation in a fuel pressure. In a case of stratified combustion by a spray guided injection, an ECU advances a fuel injection start timing of the fuel injector 4 according to the detected viscosity of the fuel. Thus, even if the viscosity of the fuel is significantly high, the fuel-rich area is well formed at a vicinity of the discharge electrode so that a preferable combustion condition can be maintained.

Abstract: A control system of an internal combustion engine provided with a first fuel injection valve that injects fuel into a cylinder of the internal combustion engine, a second fuel injection valve that injects fuel into an intake port of the internal combustion engine, an EGR passage that introduces an EGR gas from an exhaust passage of the internal combustion engine to an intake passage thereof, an EGR valve that is arranged in the EGR passage, and an obtaining unit that obtains an amount of intake air in the internal combustion engine. When the EGR valve is open, a determination is made as to whether the amount of intake air is in an increasing tendency or in a decreasing tendency with respect to a change in the cylinder injection ratio, and a value of the amount of intake air thus obtained is corrected based on the determination.

Abstract: A hybrid vehicle propulsion system and method of operation have been provided. As one example, the system comprises an internal combustion engine including at least a combustion chamber configured to propel the vehicle via at least a drive wheel, a motor configured to propel the vehicle via at least a drive wheel, an energy storage device configured to store energy that is usable by the motor to propel the vehicle, a fuel system configured to deliver gasoline and alcohol to the combustion chamber in varying relative amounts, a control system configured to operate the motor to propel the vehicle and to vary the relative amounts of the gasoline and alcohol provided to the combustion chamber in response to an output of the motor.

Abstract: A method for operating an internal combustion engine includes monitoring oxygen concentration in an exhaust gas feedstream, a mass flowrate of intake air, and a commanded fuel pulse of fuel. A blend ratio of biodiesel fuel and petrodiesel fuel of the fuel is determined. Engine operation is controlled in response to the blend ratio of biodiesel fuel and petrodiesel fuel of the fuel.

Abstract: A dual fuel common rail fuel injector includes a first and second control valve assembly and a first and second check needle. The dual fuel injector is capable of selectively injecting two different fuels such as diesel and liquefied natural gas. The first and second control valve assemblies operate using a single fuel, such as diesel, as the control medium. The dual fuel common rail injector further includes a hydraulic lock assembly.

Abstract: A fuel control system and method for providing fuel to an internal combustion engine are provided. The fuel control system generally includes at least one valve device structured to deliver a fuel supply to the engine, a first fuel source structured to provide a primary fuel to the valve device, a second fuel source structured to provide an alternate fuel to the valve device, and an electronic controller structured to control the valve device. The electronic controller controls the valve device as a function of various data to selectively deliver the primary fuel and the alternate fuel to generate a fuel supply, e.g. as a mixture of the two fuels. The data used to control the fuel supply may include GPS data, engine data, environmental data, and/or other operational data.

Abstract: A method for operating a stationary power generating plant, comprising a gas engine with at least one pre-chamber and at least one main combustion chamber, wherein the stationary power generating plant is fed a gas stream—in particular a substantially continuous gas stream—which comprises a hardly inflammable gas, wherein the gas stream is divided in the stationary power generating plant into a main stream and a partial stream, wherein the main stream is fed to the at least one main combustion chamber and wherein the partial stream is treated to increase its inflammability and is fed to the at least one pre-chamber of the gas engine, and also a stationary power generating plant with a gas engine.

Abstract: A number of systems and methods are disclosed which increase the replenishment interval for anti-knock fluid. This is especially important during activities which require a large amount of anti-knock fluid, such as towing. In some embodiments, the systems and methods are used to reduce anti-knock fluid consumption. For example, changes to engine operation, such as rich operation, spark retarding, upspeeding, and variable valve timing, all serve to reduce the amount of anti-knock fluid required to eliminate knocking. In other embodiments, the composition of the anti-knock fluid is modified, such as by using a higher octane fluid, or through the addition of water to the anti-knock fluid. In other embodiments, the replenishment interval is increased through a larger anti-knock fluid storage capacity. In one embodiment, a three tank system is used where the third tank can be used to store gasoline or anti-knock fluid, depending on the driving conditions.

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: Fuel systems and methods for controlling fuel systems in a vehicle with multiple fuel tanks are provided. An exemplary vehicle fuel system includes a first fuel tank including a first pressure sensor, and a second fuel tank. The system may further include a fuel tank isolation valve positioned to selectively decouple the first fuel tank and the second fuel tank. The system may further include an electronic controller configured to identify which of the first fuel tank and second fuel tank includes a fuel system leak by selectively decoupling the first fuel tank and the second fuel tank via the fuel tank isolation valve, responsive to an identification of the fuel system leak.

Abstract: A control device for an internal combustion engine includes an engine and a control unit. The engine can switch fuel to be used among plural kinds of fuel. The control unit delays a timing of switching the fuel to a timing of around a fuel cut in a case where switching the fuel is requested.

Abstract: Embodiments of engine systems for improved engine cooling and work production are disclosed herein. A working fluid can be injected into a combustion chamber or an engine during any portion of an energy cycle to cool the engine and/or to produce useful work in addition to work generated by combustion events in the chamber. The system can include a monitoring system configured to measure conditions within individual combustion chambers. Based on the interior conditions of the chamber, the system can adaptively inject working fluid mixtures into the engine. The engine can be part of a cascading series of engines including a primary engine and a secondary engine that receives fluids from the primary engine and generates energy from the fluids.

Abstract: A dual fuel engine operates on a gaseous fuel and a liquid fuel. The engine comprises a supply of gaseous fuel controlled by a first valve, a supply of compression ignitable liquid fuel controlled by a second valve, a control unit for controlling the supply of gaseous fuel and liquid fuel to each combustion chamber in the engine, and at least one knock sensor arranged to detect knock in each combustion chamber and to transmit an output signal proportional to the detected level of knock to the control unit. If knock is detected, the amount of gaseous fuel injected will be reduced while the amount of liquid fuel will be increased. The engine control system will subsequently adapt to the lower grade fuel and perform a calibration to operate as close as possible to the knock limit for the particular fuel.

Abstract: Aspects of the present invention relate to systems and method for converting ozone and fuel into mechanical energy and waste products. In some embodiments, a super-combustor may be used to provide a combustion engine with an improved ability to combust fuel. Certain embodiments of the invention may provide for an improved spark plug or modified engine having a super-combustor built in.

Abstract: The working gas circulation engine includes a circulation route capable of circulating gas containing the working gas from an exhaust side to an intake side of a combustion chamber and resupplying to the combustion chamber and provided with a removing device to remove a product generated with a reaction from the circulating gas, a supplying device capable of supplying plural kinds of reactant gas to the combustion chamber or the circulation route, a pressure detecting device capable of detecting pressure in the circulation route, and a control unit that controls supply amount of at least one kind of the reactant gas to be supplied from the supplying device based on the pressure in the circulation route detected by the pressure detecting device, and performs pressure control to adjust the pressure in the circulation route.

Abstract: A control apparatus for an internal combustion engine includes: a fuel property sensor which is provided between a fuel tank and a delivery pipe and which detects a component ratio of fuel; a fuel property value calculator that calculates an injector fuel property value for each cylinder using the component ratio detected by the fuel property sensor a period of time ago, which is equal to an amount of time required for the fuel to travel from the fuel property sensor to each fuel injector, as a value corresponding to the present component ratio of the fuel near the corresponding injector; and an engine-restart-time fuel injection amount calculator that calculates a fuel injection amount for each cylinder based on an engine-off duration in a case where the internal combustion engine is restarted after the internal combustion engine is stopped when the injector fuel property value varies from cylinder to cylinder.

Abstract: A microcomputer of an alcohol concentration sensor reads a first measurement value corresponding to a first frequency and reads a second measurement value corresponding to a second frequency. The microcomputer calculates a difference between the first and second measurement values. The microcomputer performs stuck failure abnormality determination when a state where the difference between the measurement values is equal to or smaller than a predetermined value continues. The microcomputer outputs a PWM signal of a specific frequency, which is different from a frequency in a case of a normality, to an engine ECU. Thus, a failure of the alcohol concentration sensor can be surely determined.

Abstract: An exhaust emission control apparatus for an internal combustion engine includes: an exhaust gas purification catalyst arranged in an exhaust gas passage of the internal combustion engine; an air/fuel ratio sensor installed on an upstream side of the exhaust gas purification catalyst and detects an air/fuel ratio of an exhaust gas discharged from the internal combustion engine; air/fuel ratio feedback control means that performs feedback control of the air/fuel ratio based on an output of the air/fuel ratio sensor; and sensor output correcting means that corrects a shift in the output of the air/fuel ratio sensor. The sensor output correcting means is configured so as to correct a shift in the output of the air/fuel ratio sensor using a lean shift amount of the air/fuel ratio sensor output in accordance with a quantity and/or a proportion of an aldehyde included in the exhaust gas.

Abstract: The fuel injection apparatus for the internal combustion engine includes: a fuel injector having a leading end portion that has an internal space in which fuel is accumulated and an injection port for injecting fuel; and an adsorbent disposed in the internal space, the adsorbent being capable of selectively adsorbing an alcohol component in a blended fuel of gasoline and alcohol. In this fuel injection apparatus, it is determined whether or not a fuel pressure is higher than a predetermined low fuel pressure when a request is issued for bringing an internal combustion engine to a stop. If it is determined that the fuel pressure is higher than the low fuel pressure, the fuel pressure is kept at the low fuel pressure for a predetermined period of time before the internal combustion engine is brought to a stop.

Abstract: A surge tank 52 is placed above an engine main body 4. Plural intake runners 51 include curved portions 51C, respectively, which are placed on one side of the engine main body 4, and sloped portions 51D extending from the surge tank 52 to the curved portions 51C. An air cleaner 7 is placed above the sloped portions 51D. A liquid fuel injection unit 8 is placed in a space between the engine main body 4 and the intake runners 51. A gaseous fuel injection unit 11 is placed in a gap between the surge tank 52 and the air cleaner 7. Gaseous fuel injection valves 103 are held by a bracket on a gaseous fuel delivery pipe 10A in a way that they are placed under the air cleaner, each of them being placed in a space between the adjacent two of the sloped portions 51D.

Abstract: A control apparatus for an internal combustion engine that can prevent, for instance, an exhaust purification catalyst from being damaged when the employed fuel is changed to a fuel having different properties during an operation. If fuel learning is incomplete while a refueling record exists, the throttle opening of an internal combustion engine operable on a fuel that is obtained by mixing alcohol and gasoline at an arbitrary ratio is limited. Limiting the throttle opening makes it possible to avoid an entry into an operation region where fuel increase is performed. This prevents air-fuel ratio feedback control from being stopped when a fuel change occurs. Consequently, the use of an improper air-fuel ratio that may damage the catalyst can be definitely avoided.

Abstract: A method for operating an engine with a fuel reformer is presented. In one embodiment a first fuel is reformed into a gaseous fuel comprising H, CO, and CH4. The engine is operated by injecting the gaseous fuel and a second fuel to a cylinder of the engine in response to an available amount of gaseous fuel, engine speed and engine load. Further, an engine actuator may be adjusted to vary cylinder charge dilution in response to the available amount of gaseous fuel.