Abstract: A method for the injection computation for an internal combustion engine, in particular for a gasoline range extender engine. This includes ascertaining an adaptation factor, which represents fuel aging, from a model of the fuel and a fuel outgassing via a tank vent and adaptation of a fuel injection quantity and/or a fuel injection time using the adaptation factor.

Abstract: An apparatus for determining an air-fuel ratio imbalance among cylinders based on an output value of an air-fuel ratio sensor, an imbalance determination parameter which becomes larger or smaller as a difference among air-fuel ratios becomes larger, and performs determining an air-fuel ratio imbalance among cylinders based on a result of a comparison between the imbalance determination parameter and a imbalance determination threshold. The determining apparatus calculates a purge correction coefficient which compensates for a change in the air-fuel ratio due to an evaporated fuel gas which is generated in a fuel tank, while the evaporated fuel gas is being introduced into an intake passage, and corrects a fuel injection amount with the purge correction coefficient FPG.

Abstract: A shift lever position determining unit determines whether a shift lever position of a vehicle satisfies predetermined conditions. If the shift lever position is determined to satisfy the predetermined conditions, a travel distance adding-up unit adds up an optimum shift lever position travel distance. If the shift lever position is determined not to satisfy the predetermined conditions, the travel distance adding-up unit adds up an inappropriate shift lever position travel distance. A fuel-saving driving rating unit rates driving by a driver based on each added-up value added up by the travel distance adding-up unit. A fuel-saving driving advice generating unit notifies the driver of fuel-saving driving advice together with a rating result in accordance with the rating result. Therefore, it is possible to encourage the driver to select an optimum shift lever position with high fuel efficiency and thereby to improve the driver's knowledge and awareness of the fuel-saving driving.

Abstract: A method for controlling variable camshaft timing is provided. In one example, an engine method comprises adjusting a variable cam actuator responsive to cam position feedback from even and uneven readings of a cam sensor. In this way, increased cam position feedback may be provided to improve cam positioning control.

Abstract: An air-fuel ratio imbalance detection apparatus includes an air-fuel ratio sensor that is arranged in an exhaust passage of an internal combustion engine and that includes an electrode and a diffusion layer provided on the electrode; an estimating unit configured to estimate or detect an output variation amount that is an amount of variation in an output of the air-fuel ratio sensor due to an influence of a pressure pulsation of exhaust gas from the internal combustion engine; and a determination unit configured to determine whether there is an air-fuel ratio imbalance among cylinders of the internal combustion engine, on the basis of the output variation amount and a determination value based on the output of the air-fuel ratio sensor.

Abstract: Systems and methods of operating an engine with a varying fuel composition. In one example, a split injection is performed during engine cranking with at least some fuel injected in the intake stroke and some fuel injected in the compression stroke. Further, a split ratio of the injection is adjusted based on the alcohol content of the injected fuel.

Abstract: Methods and systems are provided for conditioning a throttle command so that, on average, a difference between an actual airflow rate and a commanded airflow rate is substantially zero. A commanded throttle position is modified with a correction factor to also reduce a throttle angle error. By reducing engine air disturbances, engine performance is improved.

Abstract: A system for controlling a continuous variable valve lift actuator of a diesel engine and a method thereof stabilize exhaust gas and improve performance by variably controlling lift and timing of intake and exhaust valves based on combustion state and driving purpose. The method may include, recognizing a driving purpose and combustion state by detecting driving conditions, temperature of exhaust gas at predetermined locations on an exhaust pipe, and NOx concentration contained in the exhaust gas, determining target position and timing of intake and exhaust valves by applying the driving purpose and the combustion state to a predetermined map table, controlling position and timing of the intake and exhaust valves by actuating a CVVA, detecting combustion pressure in a combustion chamber, and modifying fuel injection amount according to the combustion pressure.

Abstract: An internal combustion engine including an exhaust arrangement comprises a first exhaust duct and a second exhaust duct. A valve arrangement preferably comprising separate first and second exhaust valves associated with each cylinder, to selectively direct exhaust from engine to the first exhaust duct during a first exhaust period, and to the second exhaust duct during a subsequent second exhaust period. A turbine having an inlet is connected to the first exhaust duct; and a compressor drivingly connected to and driven by the turbine, has an inlet connected to second duct. The compressor, driven by the turbine extracting energy from the exhaust, reduces the back pressure in the exhaust system reducing pumping losses, with the second duct bypassing the turbine in the second exhaust period such that the turbine also does not increase the exhaust back pressure at least during the main second exhaust phase.

Abstract: In a method for determining a vibration-optimised adjustment of an injection device of an internal combustion engine, for each cycle of the internal combustion engine, a plurality of individual injections per cylinder is carried out by the injection device, each of which is defined by a relative injection moment and an individual injection quantity. A temporal course of a resulting pressure influenced by pressure waves is determined in a fuel guiding part, and the above-mentioned adjustment is determined by variation of the injection moment of at least one individual injection and/or the individual quantity, such that the adjustment is characterized by a temporal variation of the resulting pressure, which is reduced by an at least partially destructive interference between the cited pressure waves. A corresponding device can determine a vibration-optimised adjustment of an injection device, and an internal combustion engine may have such a device.

Abstract: A fuel injection control device (ECU) for controlling injection supply of fuel to an engine is applied to an injector that has a valve body formed with a fuel injection hole, a needle accommodated in the valve body for opening and closing the injection hole, and a piezoelectric element for driving the needle such that the needle reciprocates and that can continuously adjust an injection rate in accordance with an injection command signal to the piezoelectric element. The fuel injection control device senses a fuel pressure waveform indicating a transition of fuel pressure fluctuation accompanying a predetermined injection of the injector based on an output of a fuel pressure sensor and calculates an injection command signal for approximating a predetermined injection parameter concerning the predetermined injection to a reference value of the parameter based on the sensed fuel pressure waveform.

Abstract: Methods are provided for controlling an engine in response to a pre-ignition event. A pre-ignition threshold and a pre-ignition mitigating action are adjusted based on a rate of change of cylinder aircharge. As a result, pre-ignition events occurring during transient engine operating conditions are detected and addressed different from pre-ignition events occurring during steady-state engine operating conditions.

Abstract: In one exemplary embodiment of the invention, an internal combustion engine includes a fuel system in fluid communication with a cylinder to direct a fuel flow to be mixed with air in the cylinder and an exhaust system in fluid communication with the cylinder to receive an exhaust gas produced by the combustion process, wherein the exhaust system includes an oxidation catalyst, a particulate filter downstream of the oxidation catalyst. The system also includes a control module that determines an amount of energy to be provided by at least one of: a post-injection process, hydrocarbon injector, and heating device, wherein the amount of energy is based on a desired temperature at a selected location in the exhaust system, an exhaust gas flow rate, a temperature of the received exhaust gas, a flow rate and temperature of the exhaust gas at the inlet of the oxidation catalyst.

Abstract: A control system and method of controlling operation of an internal combustion engine includes a load determination module that determines an engine load, an equivalence ratio module that determines an equivalence ratio, a correction factor module that generates a correction factor based on the engine load, the equivalence ratio, and the engine speed and an engine operation module that regulates operation of the engine based on the correction factor.

Abstract: In a method for adapting the performance of a fuel prefeed pump of a motor vehicle which has a common rail injection system and an internal combustion engine, after the ignition is switched on and before the internal combustion engine is started, adaptation values are determined and stored which are assigned to the fuel prefeed pump and describe its individual performance. After the internal combustion engine is started, the stored adaptation values are taken into consideration during the determining of an actuating signal for the prefeed pump.

Abstract: In a variable valve device for an internal combustion engine, which has a cam phase variable mechanism including a split variable function, when the operation of the internal combustion engine is in a predetermined extremely low speed and load region, the phase of a second intake cam is controlled to a more advanced position (S1) than the phase in which the closing timing of a second intake valve is in a most retarded position.

Abstract: With the use of a model expression (FIG. 9C), of which inputs include a desired value of an in-cylinder air amount that is a controlled object of a system and predetermined parameters, such as engine speed (ne), a desired throttle opening degree (?ref) required to control the in-cylinder air amount to the desired value is calculated. In this model expression, parameters, such as the engine speed (ne), that oscillate at a relatively high frequency are excluded from subjects of differentiation, and the desired in-cylinder air amount value only is included in the subjects of differentiation.

Abstract: A method for determining a cylinder air charge for an internal combustion engine includes determining engine operating parameters including an intake air charge density, an engine delta pressure as a ratio of an intake manifold pressure to an exhaust pressure, and an engine speed. An open-throttle volumetric efficiency corresponding to the engine operating parameters is determined, and a closed-throttle volumetric efficiency corresponding to the engine operating parameters is also determined. The cylinder air charge is determined using a selected one of the open-throttle volumetric efficiency and the closed-throttle volumetric efficiency.

Abstract: A fuel injection controlling system includes an accelerator manipulator. An accelerator manipulated variable detection sensor is configured to detect a manipulated variable of the accelerator manipulator. A rotation speed sensor is configured to detect a rotation speed of an engine. A throttle valve drive motor is configured to open and close the throttle valve in response to the manipulated variable. A controller is configured to control the throttle valve drive motor and to compute basic injection time (Ti) of fuel. A memory is configured to memorize, as a carbon adhesion judgment value (IXREF), a throttle opening degree (?TH) at a moment when a rotation speed (Ne) detected with the rotation speed sensor reaches a target idle rotation speed (NeIdle) by increasing the throttle opening degree (?TH). A corrector is configured to correct Ti with IXREF to correct an air-fuel ratio toward a leaner side as IXREF increases.

Abstract: Suggested is a procedure for operating a self-igniting Otto engine (OM) with at least one inlet valve (14), with one or several variably controllable outlet valves (15), with a sensor (21) for a continuous detection of an air-fuel-ratio (?) of the Otto engine (OM) and with a sensor (22) for detecting an engine speed n of the Otto engine (OM), whereby the fuel is directly injected into at least one combustion chamber (10) and whereby the Otto engine (OM) is operated in such a way, that a desired combustion focus (MFB50%set) is adjusted. The procedure is thereby characterized, in that the self-igniting moment of the fuel is influenced by an injection moment depending on a combustion focus (MFB50%set). An independent claim relates to a control unit that is customized for controlling the process of the procedure.

Abstract: A fuel injection amount control apparatus for an internal combustion engine includes an ECU that commands a learning-purpose injection when a first learning condition regarding operation state and a second learning condition regarding load connection state are satisfied, and calculates an injection performance value that corresponds to the actual injection amount based on the amount of change in rotation speed, and further determines whether a delay of the learning process is permitted based on whether the learning process, despite occurrence of the delay, can be completed before the injector performance reaches a permissible limit value, and forces, when the delay is not permitted, the load connection state to be a specific connection state so as to satisfy the second learning condition. When it is determined that the delay of the learning process is permitted, the delay is permitted until the two learning conditions are satisfied.

Abstract: A a method for automatically controlling an internal combustion engine, in which an individual accumulator pressure (pE) of a common rail system is detected in a measurement interval and stored; in which an evaluation window is determined for the stored individual accumulation pressure (pE), within which window an injection was brought about; in which, in a first step, both a representative injection start and a trial injection end are determined in this evaluation window as a function of the detected pressure values, and, in a second step, both a trial injection start and a representative injection end are determined in this evaluation window as a function of the detected pressure values; in which the representative injection start is checked for plausibility against the trial injection start; and in which the representative injection end is checked for plausibility against the trial injection end.

Abstract: A computer-implemented method is used to correct deviations between a predicted gas excess air ratio and a calculated excess air ratio in a dual fuel engine or other gas fueled compression ignition engine. The method includes determining gas excess air ratio for the engine based at least in part on at least one detected current operating parameter and calculating a predicted exhaust gas oxygen concentration engine based on the predicted gas excess air ratio. A time based filtered predicted exhaust gas oxygen concentration value may then be calculated and compared to a time-based filtered measured exhaust gas oxygen concentration value. The resultant oxygen concentration deviation value may be used to generate a corrected predicted gas excess air ratio.

Abstract: When alcohol mixing fuel is supplied to an internal combustion engine, an intake air flow rate is detected and a basic amplitude amount ? of an upstream target air-fuel ratio abyfr corresponding to this detected intake air flow rate is calculated. Next, alcohol concentration in the fuel (in more detail, ethanol concentration Cetha) and a cooling water temperature (or an intake air temperature) are detected, hydrogen concentration Ch in a mixing exhaust gas is calculated based on the detected ethanol concentration Cetha and the detected cooling water temperature (or the detected intake air temperature) amplitude gain ? corresponding to the calculated hydrogen concentration is calculated and finally, an amplitude amount (?×?) of the upstream target air-fuel ratio is calculated.

Abstract: A method for reducing particulate matter emitted by an engine is disclosed. In one example, the start of fuel injection timing is adjusted in response to a change in engine operating conditions. In particular, start of injection timing may be advanced and then retarded to promote fuel vaporization.

Abstract: A combustion apparatus (water heater) includes a combustion unit (burner) combusting fuel, at least two flame detector (flame rods) detecting whether there is a flame or not in the combustion unit, a determination unit (control device) determining whether or not there is a misfire, based on detected results of the flame detectors, and a control unit (control device) stopping supply of the fuel to the combustion unit in response to a determined result of the determination unit.

Abstract: A method for controlling air supply in a cylinder of a four-stroke internal-combustion engine with controlled ignition includes steps of: determining, in a phase prior to a suction phase, an estimate of mass of desired air to be sucked into the cylinder during the suction phase; determining, in a phase prior to the suction phase, a forecast of suction pressure during the suction phase; determining, in a phase prior to the suction phase, programming of suction of air as a function of the estimate of the mass of the desired air to be sucked into the cylinder during the suction phase and of the forecast of the suction pressure during the suction phase; and controlling, until an end of an exhaust phase, the suction of air into the cylinder by piloting a control device for implementation of an intake valve according to the programming of the suction of air.

Abstract: Methods and systems are provided for restarting an engine when a high pressure fuel pump is degraded. In response to an indication of high pressure fuel pump degradation, fuel may be injected during an intake stroke, rather than a compression stroke, for a selected number of combustion events since the engine restart. By shifting to an intake stroke injection, the engine may be started even when sufficient fuel rail pressures are not available.

Abstract: A control device for an internal combustion engine provided by the present invention is a control device which can enhance precision of realization of required torque while enhancing emission performance by positively changing an air-fuel ratio. The present control device generates a target air-fuel ratio by lessening a change speed of a required air-fuel ratio of an internal combustion engine. However, in a situation in which the required air-fuel ratio is made rich with return from fuel cut, lessening of the change speed of the required air-fuel ratio is stopped, and the required air-fuel ratio is directly outputted as a target air-fuel ratio. The control device calculates a target air quantity for realizing the required torque under the target air-fuel ratio. For calculation of the target air quantity, data in which relationship of torque generated by the internal combustion engine and an air quantity taken into a cylinder is fixed by being related to an air-fuel ratio can be used.

Abstract: A hybrid vehicle executes intermittent operation for stopping an operation of an internal combustion engine and thereafter resuming the operation in response to an operating state. An air-fuel ratio control apparatus executes air-fuel ratio feedback control for bringing an air-fuel ratio of air-fuel mixture supplied to the engine on the basis of an output of an upstream air-fuel ratio sensor and an output of a downstream air-fuel ratio sensor into coincidence with a target air-fuel ratio. The air-fuel ratio control apparatus acquires a catalyst parameter that indicates a state of the catalyst at a start of the engine through intermittent operation. The air-fuel ratio control apparatus substantially corrects the target air-fuel ratio in response to the acquired catalyst parameter in a predetermined period after a start of the engine through intermittent operation, and learns a sub-feedback amount that is calculated using the output of the downstream air-fuel ratio sensor.

Abstract: In a control device, an engine self-restart means tries the engine restart when an engine restart request is issued while the engine rotation speed is within a first rotation speed range. A pre-gear synchronizing control means executes gear rotation speed synchronization between pinion and ring gears, and then retries the engine restart when the engine restart request is issued while the engine rotation-speed is within a second rotation speed range. A pre-gear meshing control means executes gear-meshing between the pinion and ring gears and then retries the engine restart when the engine restart request is issued while the engine rotation speed is within a third rotation speed range. On detecting the engine-restart failure of the engine self-restart control, the control device prohibits the execution of pre-gear synchronizing control until a predetermined time counted form the failure detection time is elapsed, and executes the pre-gear meshing control after the predetermined time period is elapsed.

Abstract: In a hydraulic system equipped with a main flow passage for feeding oil to each of lubricated engine parts and a branch passage branched from the main flow passage, a control valve apparatus is provided for adjusting a flow rate of the oil flowing through a portion of the main flow passage downstream of the branched point. The control valve apparatus is configured to control the flow rate to a large flow-rate side of a variable flow-rate range, until a hydraulic pressure of the oil flowing through the main flow passage becomes greater than or equal to a predetermined pressure value after the engine has been started from its stopped state. The control valve apparatus is further configured to control the flow rate to a small flow-rate side of the variable flow-rate range, when the predetermined pressure value has been reached.

Abstract: Controlling a vehicle responsive to reductant conditions is provided. The method for controlling a vehicle having an engine with an exhaust, the exhaust having a reductant injection system including a reductant storage vessel, the engine further having a fuel system including a fuel storage vessel, may include under degraded reductant conditions, restricting vehicle motion in response to a fuel refill of the fuel storage vessel.

Abstract: An apparatus and method for improving vehicle performance by application of pneumatic boost to vehicle engines, including diesel engines having at least one turbocharger supplying air to the engine, in a manner which increases engine torque output while minimizing the potential for exceed various operating limits to the maximum practicable extent. The vehicle's pneumatic booster system controller implements strategies for shaping the rate of the air injection during a boost event, tailoring the air injection to obtain maximum engine torque output while respecting the operating limits, by controlling the timing, duration, quantity and/or injection pattern during a boost event to achieve a refined distribution of compressed air injection over the course of the boost event to provide desired engine torque output and fuel efficiency while minimizing the potential for exceeding a wide variety of operation limits, regulatory, engineering and passenger comfort limits.

Abstract: A cylinder-to-cylinder air/fuel ratio imbalance determination system obtains an imbalance determination parameter that increases or decreases as a difference between the air/fuel ratios of different cylinders increases, based on output values of an air/fuel ratio sensor, and makes a cylinder-to-cylinder A/F imbalance determination, based on the result of comparison between the imbalance determination parameter and a threshold value for imbalance determination. The determination system changes the amount of fuel injected into one or more of the cylinders so as to create a forced imbalance condition in which the air/fuel ratio of a particular cylinder deviates from the air/fuel ratio of the remaining cylinders, and obtains an air/fuel ratio sensor evaluation parameter (e.g., rate of change ?AF of the detected air/fuel ratio) in this condition.

Abstract: A gas turbine control method and device to restrain combustion vibration more precisely by alleviating the relationship between the composition or heat quantity of the fuel and the combustion vibration characteristic and by grasping the combustion vibration characteristic more accurately. The combustion vibration generated by a burner of the gas turbine and the composition or heat quantity and other plant status amounts of fuel supplied to the burner are detected. The combustion vibration characteristic is grasped based on the detected values. When the combustion flow rate or air flow rate supplied to the burner is increased/decreased to obtain operation condition under which no combustion vibration occurs, the detected values of the combustion vibration as well as the composition or heat quantity and other plant status amounts of the fuel are divided and stored in multiple databases corresponding to the value of the composition or heat quantity of the fuel.

Abstract: When a detected value for detecting a rich imbalance in air-fuel ratio among cylinders in a state where an intake air amount of an engine falls within a low amount region is lower than a first threshold corresponding to the intake air amount and is higher than or equal to a second threshold corresponding to the intake air amount, an HV-ECU controls the engine such that the intake air amount falls within a high amount region, and controls a motor generator such that an electric power corresponding to a power increase amount is consumed. When the intake air amount falls within the high amount region, the HV-ECU detects a rich imbalance in air-fuel ratio among the cylinders by comparing the detected value with a third threshold corresponding to the intake air amount.

Abstract: A method for reducing the thermal load of an internal combustion engine without substantially reducing its power output is described. The method includes adjusting an engine air-fuel ratio responsive to one or more of a charge air over-temperature, a coolant over-temperature and an engine efficiency parameter.

Abstract: In a method for determining a control parameter for a fuel injector of an internal combustion engine, the problem of enabling more precise determination of the control parameter, even if the fuel pressure (FUP) present on the fuel injector varies, is solved in that the fuel pressure (FUP) present on the fuel injector during the injection (I1, I2, I1?, I1?) is concluded while allowing for the time of the fuel pressure value detection and/or the crankshaft angle position of the internal combustion engine during the detection of the fuel pressure value, and that the control parameter is determined based on the fuel pressure (FUP) that was concluded.

Abstract: A variety of skip fire engine controllers and control techniques are described. In some preferred embodiments, a skip fire engine controller is provided that includes a firing fraction calculator, an engine settings controller, a firing fraction adjuster and a firing controller. The firing fraction calculator determines a reference firing fraction indicative of a firing fraction suitable for delivering a desired engine output at a reference working chamber firing output. The engine settings controller is arranged to set selected engine settings. The firing fraction adjuster determines an adjusted firing fraction that scales the reference firing fraction appropriately such that the engine will deliver the desired engine output at the current engine settings even when the actual working chamber firing outputs do not equal the reference working chamber firing output. The firing controller direct workings chamber firings in a skip fire manner that delivers the adjusted firing fraction.

Abstract: A method and system of predictive model control of a controlled system with one or more physical components using a model predictive control (MPC) model, determining an iterative, finite horizon optimization of a system model of the controlled system, in order to generate a manipulated value trajectory as part of a control process. At time t sampling a current state of the controlled system a cost function minimizing manipulated variables trajectories is computed with the MPC model for a relatively short time horizon in the future, wherein the MPC uses a quadratic programming (QP) algorithm to find the optimal solution, and wherein the QP algorithm is solved using an Active Sets solver (AS) class algorithm with simple constraints based on gradient projection and using Newton step projection. A move of the manipulated value trajectory is implemented and the control process is moved forward by continuing to shift the prediction horizon forward.

Abstract: A method for transferring existing data from a source motor to a target motor includes retrieving the existing data from the source motor, optionally converting the existing data into a new format, and at least one of storing, erasing, writing, overwriting, or replacing software and/or data on the target motor such that the existing data is stored on the target motor in a format compatible with the target motor.

Abstract: Embodiments for controlling a gas turbine engine to minimize combustion dynamics and emissions are disclosed. Methods and an apparatus are provided for controlling the gas turbine engine where a compressor inlet temperature is measured and a turbine reference temperature is calculated in real-time and utilized to determine the most-efficient fuel splits and operating conditions for each of the fuel circuits. The fuel flow for the fuel circuits are then adjusted according to the identified fuel split.

Abstract: An air-fuel ratio imbalance determination apparatus for a multi-cylinder internal combustion engine includes an air-fuel ratio sensor with a catalyst layer disposed in an exhaust passage of the multi-cylinder internal combustion engine; and a control unit configured: to perform determination regarding an air-fuel ratio imbalance state among cylinders of the multi-cylinder internal combustion engine based on an amount of change per unit time in an air-fuel ratio detected by the air-fuel ratio sensor; to execute an air-fuel ratio enrichment control using an air-fuel ratio enrichment amount; and to correct a learned imbalance value when the air-fuel ratio enrichment amount is smaller than a predetermined determination threshold value in a case where an engine operation state is in an imbalance learning range during execution of the air-fuel ratio enrichment control.

Abstract: An air-fuel ratio imbalance detecting device for an internal combustion engine, which detects a rich imbalance in air-fuel ratio among a plurality of cylinders on the basis of a variation per unit time in air-fuel ratio that is detected by an air-fuel ratio sensor provided in an exhaust passage of the internal combustion engine, includes an electronic control unit that normalizes the variation per unit time in air-fuel ratio with a constant associated with a rotation speed and load factor of the internal combustion engine and that, when the normalized value is smaller than a predetermined threshold, determines that a rich imbalance in air-fuel ratio has been detected among the cylinders.

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 method for operating an internal combustion engine comprising an exhaust gas cleaning system that includes a SCR catalyst. In conjunction with a cold start and/or a warm-up of the internal combustion engine, the internal combustion engine is operated using a cold start engine operation method having predefineable values for predefineable operating parameters of the internal combustion engine. An amount of nitrogen oxides stored in the SCR catalyst is estimated, and the cold start engine operation method is activated when the estimation indicates that the nitrogen oxide storage amount exceeds a predefineable nitrogen oxide storage amount limit value.

Abstract: A control apparatus for an internal combustion engine is employed for a multi-cylinder internal combustion engine. The control apparatus includes a variable valve operating mechanism which changes a valve characteristic of an engine valve; a valve stop mechanism which stops opening/closing of the engine valve in at least one cylinder; and a controller which executes a variable valve control that makes an actual value of the valve characteristic match a target value by executing a hydraulic pressure control for the variable valve operating mechanism, and which operates the valve stop mechanism so that a reduced-cylinder operation is performed when an engine operating state is in a preset reduced-cylinder operation region. If it is determined that a pressure of hydraulic fluid supplied to the variable valve operating mechanism satisfies a preset condition when the engine operating state is in the reduced-cylinder operation region, the controller prohibits the variable valve control.

Abstract: A first control system for an engine includes first and second control modules. The first control module determines first and second fuel masses for first and second fuel injection systems of the engine, respectively, and that controls the first fuel injection system to inject a first fuel based on the first fuel mass. The second control module controls the second fuel injection system to inject a second fuel based on the second fuel mass. A second control system for an engine includes first and second control modules. The first control module controls a first fuel injection system of the engine to inject a first fuel and selectively disables at least one of a plurality of components of a second fuel injection system of the engine. The second control module controls the second fuel injection system to inject a second fuel.

Abstract: An internal combustion engine can be operated by a fuel mixture consisting of a base fuel and an alternative fuel. Concentration values (ETH_PERC) of the alternative fuel are determined in at least two different ways for operating the internal combustion engine. A reliable concentration value of the alternative fuel is determined depending on the various determined concentration values (ETH_PERC).