Abstract: In a malfunction judging method for a fuel feeding apparatus in an internal-combustion engine, a feedback correction value is calculated based on an air-fuel ratio parameter and a predetermined feedback control algorithm. In which region a load parameter exists among a first region in which only a first fuel feeding apparatus is used, a second region in which only a second fuel feeding apparatus is used, and a third region other than the first region and the second region is determined. The feedback correction value calculated in a case where the load parameter exists in the first region is determined as a first learned value using a predetermined first learning method. The feedback correction value calculated in a case where the load parameter exists in the second region is determined as a second learned value using a predetermined second learning method.

Abstract: An air-fuel ratio control device has an open loop controller which controls an air-fuel ratio to be a target air-fuel ratio, a feedback controller that shifts the target air-fuel ratio to a logical air-fuel ratio, and feedback controls the air-fuel ratio to be the logical air-fuel ratio by using a feedback correction coefficient determined based on an output of an O2 sensor, an average value calculator that calculates an average value of the feedback correction coefficient when the output of the O2 sensor reverses from a lean side to a rich side and from the rich side to the lean side in a feedback control by the feedback controller, and a learned value calculator that calculates a learned value based on the average value at a time when the average value calculated by the average value calculator becomes substantially constant.

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 object of the invention is to provide a feedback control system that calculates a P term and an I term on the basis of a deviation between a target value and a measured value of a control amount, and calculates a correction amount to be applied to an operation amount of a control subject on the basis of a PI term, which is a sum of the P term and the I term, wherein divergence of the I term in a condition where the PI term is restricted by a guard is prevented while improving a convergence property of the I term following removal of the restriction applied to the PI term by the guard.

Abstract: A diagnostic for identifying cylinder to cylinder air/fuel ratio faults of an engine having closed loop fuel control. Air mass flow is accumulated for a plurality of load bands on the engine load/speed map, and for each load band a rich/lean air fuel ratio is determined at a mass threshold. This threshold data is processed and compared with fixed data to determine whether any cylinder of an engine is experiencing an air/fuel ratio fault which is substantially different to the remainder.

Abstract: In a method for operating an injection valve having a longitudinal axis, an injection needle, a control valve and an actuator embodied as a solid body actuator, wherein the actuator acts on the control valve and the control valve acts on the injection nozzle, various pre-defined quantities of electrical energy are supplied to the actuator in a plurality of adaptation flows in order to modify an axial length of the actuator. This electrical energy is defined such that an axial position of the injection nozzle remains unchanged. In correlation with the respective adaptation flow, and following the energy supply associated with the respective adaptation flow, a first and second voltage value are detected and a voltage differential value is then determined which is compared with a pre-defined threshold value and, on the basis of the comparison, at least one control of the actuator is adapted to the injection of fluid.

Abstract: A low-pressure loop EGR device includes an electronic control unit. When an off signal is inputted from a key switch as a stop warning signal to give notice that a supercharged engine is about to stop, the electric control unit controls an EGR valve so as to close an EGR passage, and then controls a nozzle actuator so as to turn multiple variable nozzles in a narrowing direction.

Abstract: Methods and systems are disclosed for fuel drift estimation and compensation using exhaust oxygen levels and fresh air flow measurements. An actual fueling to the engine cylinders is determined from the exhaust oxygen level and fresh air flow to the internal combustion engine. The actual fueling is compared to an expected fueling based on the fueling command provided to the internal combustion engine. The difference between the actual fueling and expected fueling is fuel drift error attributed to changes or drift in the fuel injection system and is used to correct or compensate future fueling commands for the fuel drift.

Abstract: A control apparatus for an internal combustion engine having a means for performing a model calculation to calculate, as an exhaust temperature calculation value, the temperature of exhaust gas in an exhaust branch tube at the time of starting an engine, using a model representing the temperature behavior of the exhaust gas in the exhaust branch tube during stop of an engine; and an exhaust temperature actual measurement value output means for detecting the temperature of exhaust gas in the exhaust branch tube, and outputting the detected temperature as an exhaust temperature actual measurement value, wherein the model includes at least one parameter.

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

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

Abstract: Methods and systems for optimizing a performance of a vehicle engine are provided. The method includes determining an initial value for a first engine control parameter based on one or more detected operating conditions of the vehicle engine, determining a value of an engine performance variable, and artificially perturbing the determined value of the engine performance variable. The initial value for the first engine control parameter is then adjusted based on the perturbed engine performance variable causing the engine performance variable to approach a target engine performance variable. Operation of the vehicle engine is controlled based on the adjusted initial value for the first engine control parameter. These acts are repeated until the engine performance variable approaches the target engine performance variable.

Abstract: A first parameter correlated with a degree of fluctuation of output from an air-fuel ratio sensor is calculated, and whether or not the calculated first parameter has a value between a predetermined primary determination upper-limit value ?1H and a primary determination lower-limit value is determined. Such forced active control as reduces an air-fuel ratio shift in one of the cylinders which is subjected to a most significant air-fuel ratio shift is performed when the calculated first parameter is determined to have a value between the predetermined primary determination upper-limit value and the primary determination lower-limit value. A first parameter is calculated while the forced active control is in execution. The calculated first parameter is compared with a predetermined secondary determination value to determine whether or not variation abnormality is present.

Abstract: A control system includes an engine control module that generates fuel injector command signals for fuel injectors of an engine and engine parameter signals that indicate operating characteristics of the engine. A fuel injector control module communicates with the engine control module via a network. The engine control module transmits the engine parameter signals to the fuel injector control module via the network. The fuel injector control module generates compensated fuel injector signals based on the fuel injector command signals and the engine parameter signals. The engine control module may generate fuel injector command signals for a gaseous fuel mode based on signals received from the fuel injector control module.

Abstract: When the ratio of the amount of vaporized fuel (purge amount) to be introduced into an intake passage of an engine from a fuel tank through a purge passage pipe, a purge control valve, etc. to the total amount of fuel (total fuel amount) to be supplied to the engine is large, an abnormality determination system acquires, as a parameter Pon, the air-fuel ratio imbalance index value that increases as the difference between the air-fuel ratios of the respective cylinders increases. When the purge amount is small relative to the total fuel amount, the determination system acquires the air-fuel ratio imbalance index value as a parameter Poff. When the difference between the parameters Pon and Poff is less than a predetermined value and at least one of these parameters is greater than a predetermined threshold value, the determination system determines that an inter-cylinder air intake amount variation abnormality is occurring.

Abstract: A method for assessing a method of functioning of a fuel injector in response to the application of a control voltage to at least one actuator of the fuel injector, including the steps of applying the control voltage to the at least one actuator of the fuel injector for a no-torque-generating injection into an engine, determining a fuel content in an exhaust tract disposed at an engine, comparing the determined fuel content with a specified comparison value, and assessing the method of functioning of the fuel injector based on the comparison result. Furthermore, also described is an evaluation device for assessing a method of functioning of a fuel injector in response to the application of a control voltage.

Abstract: An air-fuel ratio control apparatus for an internal-combustion engine includes an air-fuel-ratio sensor, a control-input calculator, an air-fuel-ratio controller, and a gain calculator. The air-fuel-ratio sensor is disposed in an exhaust channel in the internal-combustion engine and is configured to detect an air-fuel ratio in exhaust gas. The control-input calculator is configured to calculate a control input in accordance with an output value of the air-fuel-ratio sensor. The air-fuel-ratio controller is configured to perform a feedback control using the control input such that the output value of the air-fuel-ratio sensor reaches a target value. The gain calculator is configured to calculate a gain in accordance with the output value when the output value is leaner than the target value. The gain is to be used in calculating the control input.

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: An abnormality detection apparatus for a multi-cylinder internal combustion engine changes a fuel injection quantity of a predetermined target cylinder to detect an abnormality of an internal combustion engine based on values of rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity. The abnormality detection apparatus corrects the values of the rotational variations relating to the target cylinder detected before and after the change of the fuel injection quantity based on at least one of the number of revolutions of the engine and an engine load at a corresponding detection time.

Abstract: Methods and systems for an engine system including an exhaust gas sensor are disclosed. In one example, under a first engine fueling condition, an air-fuel ratio correction factor is determined based on an expected air-fuel ratio and an actual air-fuel ratio. During a second engine fueling condition and a third engine non-fueling condition, fuel alcohol content and ambient humidity, respectively, are determined based on the exhaust gas sensor and corrected based on the air-fuel ratio correction factor.

Abstract: An air-fuel ratio control apparatus includes a catalytic converter disposed at a position downstream of an exhaust gas aggregated portion; a downstream air-fuel ratio sensor disposed in an exhaust passage at a position downstream of the catalytic converter; first feedback amount updating means for updating a first feedback amount to have an output value of the downstream air-fuel ratio sensor coincide with a target downstream-side air-fuel ratio based on the output value of the downstream air-fuel ratio sensor; and a learning means for updating a leaning value of the first feedback amount in such a manner that the leaning value brings in a steady-state component of the first feedback amount based on the first feedback amount.

Abstract: Provided is an internal combustion engine system controller, including a sub-feedback learning section, a state determining section, and a learning update-speed setting section. The state determining section determines, to which of at least three states including: (a) a stable state in which a fluctuating state of a sub-feedback learning value is stable; (b) an unstable state in which the fluctuating state greatly fluctuates; and (c) an intermediate state between the stable state and the instable state (may be referred to as sub-stable state), the fluctuating state corresponds. The learning update-speed setting section sets an update speed of the sub-feedback learning value in accordance with the result of determination by the state determining section. Further, the learning update-speed setting section suppresses the occurrence of hunting of the sub-feedback learning value.

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: The present invention relates to a fuel supply control apparatus and a fuel supply control method for controlling an electric fuel pump, in an internal combustion engine provided with the electric fuel pump for pumping fuel to a fuel injection valve and a pressure regulator for regulating fuel pressure at set pressure. When a learning condition of a drive voltage for the electric fuel pump is established, the drive voltage is temporarily reduced and a change amount ?AF of an air-fuel ratio at the time is detected. Then, if the change amount ?AF is within a first threshold ?AF1, the drive voltage is reduced, whereas, if the change amount ?AF is greater than a second threshold ?AF2 which is equal to or greater than the first threshold ?AF1, the drive voltage is increased.

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: 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: Fuel reforming catalysts 28 generate a hydrogen-containing reformed gas when they come into contact with exhaust gas that contains a reforming fuel. Upstream and downstream air-fuel ratio sensors 58, 60 are respectively installed upstream and downstream of the fuel reforming catalysts 28. The upstream air-fuel ratio sensor 58 outputs a upstream sensor signal in accordance with oxygen concentration. The downstream air-fuel ratio sensor 60 outputs a downstream sensor signal in accordance with oxygen concentration and hydrogen concentration by using zirconia's oxygen detection capability and a change of a diffusion layer's hydrogen-concentration-dependent oxygen detection capability. An ECU 50 detects the hydrogen concentration without being affected by the oxygen concentration through the use of the upstream sensor signal in which only the oxygen concentration is reflected and the downstream sensor signal in which the oxygen concentration and hydrogen concentration are reflected.

Abstract: An air-fuel ratio control system of an internal combustion engine includes a controller that performs air-fuel ratio feedback control through main feedback control and sub feedback control based on the concentrations of oxygen in exhaust gas upstream and downstream of a catalyst respectively, and the controller stores a constant component of a sub feedback correction value of the sub feedback control as a sub feedback learned value, and sets a feedback target value of the main feedback control to values that are different depending on whether or not exhaust gas is recirculated into intake air. When the constant component of the sub feedback correction value obtained when the amount of recirculated exhaust gas is short of its required amount is stored as the sub feedback learned value, the controller corrects the feedback target value of the main feedback control when the recirculation of exhaust gas is not conducted.

Abstract: A control method and a control device of an engine are introduced. During the process of the engine controlling, the control unit does the adaptive learning for the actual target value of the feedback of different aims, and following the dynamic spectrogram generation strategy optimizing compares the adaptively learning parameter of the same working status and the same time with the basic spectrogram parameter. If the compared result doesn't meet the condition, then keep the basic spectrogram parameter. And if it meets the condition, then the engine generates the dynamic spectrogram parameter. Based on the dynamic spectrogram combination strategy, the engine combines the basic spectrogram parameter and the dynamic spectrogram parameter generated to the combined spectrogram parameter instead of the basic spectrogram parameter.

Abstract: To partially supplant the use of fossil fuels in diesel engines, oxygen-containing fuels, such as biodiesels, are proposed as blending agents in diesel fuel. Engine calibration coefficients to control EGR rate, timings and quantities of fuel injection pulses, turbocharger boost, etc, can be determined to compensate for the lower energy content of such oxygenate blends compared to diesel fuels. According to an embodiment of the disclosure, the fuel quantity of each of multiple injection pulses is increased proportionally to compensate for the impact of oxygenates. An adjustment in the fuel injection quantity is performed in response to a new tank of fuel and the adjustment is applied for that tank of fuel. A fuel compensation factor (FCF) can be determined based on the actual amount of fuel injected compared to the expected amount of diesel fuel at the present operating condition.

Abstract: An engine system includes a first module that determines a cylinder of an engine to be in one of M prediction types and generates a distance from intake signal indicating a number of prediction steps the cylinder is away from an intake stroke. M is an integer greater than or equal to 3. A second module determines a cycle type of the cylinder. The cycle type indicates a number of combustion cycles the cylinder has experienced from a last restart of the engine. A cylinder air charge module estimates an air mass within the cylinder based on the distance from intake signal and the cycle type.

Abstract: An engine in which a fluctuation in the amount of fuel injection is reduced in the entire operating tolerance of the engine. The engine (1) has an engine body (5) provided with a turbocharger (7), an engine speed sensor (21), a turbo sensor (22), a boost sensor (23), and an ECU (20) for correcting the amount of fuel injection. A control means recognizes an engine speed, a supercharging pressure, a supercharger speed, a fuel injection amount and corrects the fuel injection amount.

Abstract: Systems and methods for continuous automatic adjustment of a control set point of an air-fuel ratio controller of a rich burn engine so as to maintain emissions within a desired range. In an embodiment, a NOx sensor is placed in the exhaust outlet from an exhaust catalyst and the NOx exhaust sensor output is continuously monitored while adjusting the control set point between rich and lean in order to minimize the output from the NOx sensor. Corrections may be continuously made to the set point during operation of the engine to compensate for changes in environmental conditions, engine loads, and other factors.

Abstract: An internal combustion engine (1) has a fuel tank (18) and a fuel vapor reservoir (25). According to the method during the tank vent period—before opening the tank vent valve (28) a reference value is updated if a condition is met, and otherwise the existing reference value is maintained, —before opening the tank vent valve (28) an opening period is determined as a function of at least one variable, —the tank vent valve (28) is controlled such that the flow achieves the target flow value by the end of the opening period that was determined, —the load level of the fuel vapor reservoir (25) is computed based on the reference value, —a fuel amount is computed based on the load level, —and the fuel amount to be metered by the injection valve (22) is corrected based on the computer fuel amount.

Abstract: A method for operating a hybrid drive of a motor vehicle in particular. An internal combustion engine is connected to a generator via a force-conducting connection. In a learning mode, the generator is operated as a motor and drives the internal combustion engine. In this learning mode, a so-called zero quantity calibration is performed.

Abstract: A control device for an internal combustion engine includes: an abnormality determination portion determining the presence of an abnormality in a fuel system, such as an injector, by comparing an air-fuel ratio detected by an A/F sensor and a learning value of the air-fuel ratio with a preset abnormality determination value; an alcohol concentration estimating portion estimating the alcohol concentration in fuel based on the air-fuel ratio detected by the A/F sensor and the learning value; and an abnormality determination value changing portion changing the abnormality determination value depending on the alcohol concentration estimated by the alcohol concentration estimating portion.

Abstract: An internal combustion engine has an exhaust gas tract with a first and a second exhaust gas catalyst downstream of the first one, a first exhaust gas sensor, which is disposed upstream or in the first catalyst, and a second exhaust gas sensor, which is disposed downstream of the first catalyst and upstream of the second catalyst. During trailing throttle operation, the measurement signal of the second sensor is monitored for a signal characteristic that is typical of a maximum possible saturation state with oxygen that the first catalyst can achieve, upon which a characteristic variable is determined for a saturation state of the second catalyst with oxygen as a function of an engine operating variable. Outside the trailing throttle operation, an enrichment mode is controlled by enriching the air/fuel mixture, specifically as a function of the characteristic variable for the saturation state of the second catalyst with oxygen.

Abstract: An air-fuel ratio control device of an internal combustion engine is provided. The control device includes a learning section, a correction section, and an inhibiting section. When an execution condition is met, the learning section learns, as a deviation amount learned value, a constant deviation amount between a correction amount and its reference value in different manners between a case in which the lift amount of the intake valve is in a first lift amount region used only when the execution condition is not met and a case in which the lift amount is in a second lift amount region used only when the execution condition is met. The learning section computes and stores the relationship between the deviation amount and the lift amount based on the deviation amount learned value. A correction section computes the deviation amount correction value from the stored relationship based on the lift amount, and corrects the fuel injection amount command value using the deviation amount correction value.

Abstract: An amount of fuel injected into an internal combustion engine is controlled to adjust an air-fuel ratio. An air-fuel ratio sensor is disposed upstream of a three-way catalyst. An ammonia sensor is disposed downstream of the three-way catalyst. Main feedback control based on the air-fuel ratio sensor is performed such that the air-fuel ratio of exhaust gas becomes close to a target air-fuel ratio in the neighborhood of a stoichiometric air-fuel ratio. Sub-feedback control is performed on the basis of an output value of the ammonia sensor.

Abstract: An abnormality diagnosis apparatus for diagnosing abnormality of a secondary air supply assembly includes an abnormality diagnosing unit, an air-fuel ratio learning/correcting unit, a learning degree computing unit, and a prohibition unit. The abnormality diagnosing unit diagnoses abnormality of the secondary air supply assembly based on an output of the air-fuel ratio detecting unit. The air-fuel ratio learning/correcting unit learns variation of an air-fuel ratio control system of the engine and corrects variation of an air-fuel ratio based on a result of learning the variation of the air-fuel ratio control system. The learning degree computing unit computes a learning degree, by which the air-fuel ratio learning/correcting unit learns the variation of the air-fuel ratio control system. The prohibition unit prohibits the abnormality diagnosis or makes a diagnostic result invalid when the learning degree is equal to or less than a predetermined value.

Abstract: The device including: a fuel correction value calculating unit for calculating a correction value for a fuel injection quantity so that an actual air-fuel ratio becomes equal to a target air-fuel ratio; a fuel switching detecting unit for detecting that fuel switching has occurred; a fuel property estimating unit for setting a period, in which there is a possibility that a fuel property changes, as a property change period when the fuel switching is detected to calculate a fuel property correction value corresponding to another correction value for the fuel injection quantity based on the correction value within the property change period; and a property change judging unit for judging whether or not a change in the correction value is due to the change in the fuel property in a case where the correction value becomes out of a predetermined range even though the property change period is not set.

Abstract: A method for controlling an internal combustion engine includes: providing a setpoint value of at least one combustion attribute on the basis of a setpoint value characteristics map; determining from a control variable characteristics map a value of a characteristics-map-based control variable for controlling the engine; ascertaining with the aid of a data-based model a value of a modified control variable for controlling the engine, the data-based model specifying a predicted combustion attribute as a function of a real value of the combustion attribute of the preceding combustion, and the value of the modified control variable for controlling the engine being ascertained from the predicted combustion attribute; and providing a real control variable set to a value that is a function of the value of the characteristics-map-based control variable and/or the value of the modified control variable.

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: An air-fuel ratio control system of a multi-cylinder internal combustion engine provided with a throttle valve and opening characteristic control means, which system performs feedback control of an air-fuel ratio based on an output of a sensor detecting an air-fuel ratio of exhaust gas and is capable of performing more accurate air-fuel ratio control, is provided. In the feedback control, the relationship of the output of the sensor and a feedback value is corrected based on a feedback learning correction value learned and determined based on the output of the sensor during the feedback control, and, when newly learning the feedback learning correction value, the intake air amount is controlled by only the throttle valve.

Abstract: A method for operating an internal combustion engine is provided and at least a first map of prefixed first values is predetermined, each prefixed first value being a function of a prefixed nominal fuel quantity (Qecu—prefix). The method includes, but is not limited to the steps of determining a nominal fuel quantity (Qecu) for one injection, calculating an actual, torque forming, injected fuel quantity of the injection (QUEGO) and calculating at least one first parameter (Qdelta) which is related to the actual, torque forming, injected fuel quantity of the injection (QUEGO). After that, the nominal fuel quantity (Qecu) is modified according to the value of the at least one first parameter (Qdelta) so as to obtain a corrected fuel quantity (QecuCorr) that corresponds to the actual fuel quantity injected during the injection.

Abstract: An air-fuel ratio control apparatus includes a learning unit learning amounts of divergence of a correction amount from a reference value thereof respectively as to a plurality of set lift amount regions as divergence amount learning values, a correction unit calculating a divergence amount correction value and correcting a fuel injection amount command value, and a reflection unit reflecting a learning result of the divergence amount learning value of a specific one of the plurality of the set lift amount regions on the divergence amount learning value of another one of the lift amount regions when there is a history indicating that the divergence amount learning value of the specific one of the lift amount regions has been learned and there is no history indicating that the divergence amount learning value of that another one of the lift amount regions has been learned.

Abstract: A system and method for using a sliding mode control algorithm to control flow rates from air handling actuators and fuel injectors of an internal combustion engine. The sliding mode control is based on an engine model that represents the engine in terms of pressure and oxygen content states of the intake and exhaust manifolds (as a linear term) and controllable flow rates (as a nonlinear term).

Abstract: In controlling an engine, an amount of an intake charge provided, during operation of the engine, to a combustion chamber of the engine is determined. The intake charge includes an air component, a fuel component and a diluent component. An amount of the air component of the intake charge is determined. An amount of the diluent component of the intake charge is determined utilizing the amount of the intake charge, the amount of the air component and, in some instances, the amount of the fuel component. An amount of a diluent supplied to the intake charge is adjusted based at least in part on the determined amount of diluent component of the intake charge.

Abstract: With an internal combustion engine (1) there is the problem that the fuel-air mixture directed into the combustion chamber of the cylinders (2) can be substantially influenced by manufacturing tolerances and ageing of the fuel injectors and uneven distribution is thus created. The uneven distribution is individually determined for each cylinder (2) depending on the operating mode of the internal combustion engine (1) (homogenous operation, stratified operation), wherein either the exhaust gas is analyzed and a corresponding emission value is determined therefrom or that a value is individually determined for each cylinder (2) for the operational roughness of the internal combustion engine (1). These values are compared with a limit value predetermined for the internal combustion engine (1) and upon exceeding of the predetermined limit value a fault entry in a fault memory (9) is made for the cylinder (2) concerned.