Abstract: A fuel injection control device for a multi-fuel engine includes a corrector and a reviewer. An alcohol concentration learning unit is provided to learn an alcohol concentration in an injected fuel based on an oxygen concentration detected in an exhaust gas. A fuel injection amount controller is provided to control a fuel injection amount based on a learning value corresponding to the oxygen concentration. The corrector is configured to reduce the fuel injection amount corresponding to the learning value for a predetermined time period when the learning value is higher than a threshold value when an engine is started. The reviewer is configured to review the learning value to provide a revised learning value based on the oxygen concentration while the corrector reduces the fuel injection amount. The fuel injection amount is controlled based on the revised learning value after the corrector reduces the fuel injection amount.

Abstract: A vehicle-mounted engine control apparatus can accurately measure the resistance value of a label resistor arranged in an exhaust gas sensor for correcting characteristic variation thereof by using a reduced number of wires. An electric heater of the exhaust gas sensor, which is powered from a second power supply wire, as well as the label resistor and air fuel ratio measurement elements are connected to the apparatus which is powered from an on-vehicle battery through a first power supply wire. A power feed voltage of the apparatus is input to a multichannel AD converter through voltage dividing resistors, so that a positive end potential of the label resistor is measured alternatively. A negative end potential of the label resistor is input to the converter as a divided voltage thereof with a fixed resistor. The label resistance value is calculated from a fixed resistor current and a label resistor voltage.

Abstract: A control system for an engine having N cylinders in first and second banks includes a catalyst heat module and a fuel control module. N is an integer greater than two. The catalyst heat module selectively operates the engine in a catalyst heat mode to heat a catalyst. The fuel control module, throughout a fuel injection sequence for each of the N cylinders, adjusts a first air/fuel (A/F) ratio for the first bank to a rich value and adjusts a second A/F ratio for the second bank to a lean value.

Abstract: An apparatus includes: an control portion that controls fluctuating the air/fuel ratio; a data acquisition portion that acquires a responsiveness parameter during change of output of the sensor between a rich peak to a lean peak; and a determination portion that determines presence/absence of abnormality of the sensor based on an abnormality criterion value and a data average. When the number of the acquired data becomes equal to or greater than a first number, if the number of the acquired data during a large intake-air-amount of an engine is greater than or equal to a second number, the determination portion determines the presence/absence of abnormality, or if the number of the acquired data during the large intake-air-amount is less than the second number, the determination portion does not determines that, but acquires the data until the number of the acquired data during the large intake-air-amount reaches the second number.

Abstract: An internal combustion engine has an exhaust gas catalyst, a first exhaust gas sensor that is arranged for use in lambda control, and a second sensor that is arranged for trim control. The measuring signal of the second sensor is used to determine a NOx quality value depending on the HC quality value and the NOx correction factor. A lambda quality value is determined depending on an actual value and a basic set value of the air/fuel ratio. An error indicator is determined depending on the lambda quality value and the NOx quality value, the error indicator being representative of a mixture component error in a first range and being representative of an exhaust gas catalyst error in a second range. At least one control parameter of a trim control and/or the trim set value of the trim control is adapted depending on the NOx correction factor.

Abstract: An exhaust catalyst is charged with oxygen until saturated. A given first rich air/fuel ratio is set in a combustion chamber of a cylinder. A first oxygen storage capacity value is determined depending on the measured signals from first and second exhaust probes. The exhaust catalyst is charged with oxygen until saturated. A given second rich air/fuel ratio is set in the combustion chamber of the cylinder. A second oxygen storage capacity value is determined depending on the measured signal from the first and second exhaust probe. A corrected oxygen storage capacity value is determined depending on the first and second oxygen storage capacity values.

Abstract: A method of regulating the actual lambda value for an internal-combustion engine of a motor vehicle in a closed control loop is provided. A lambda setpoint is transferred to a controller for influencing an injection calculation for the internal-combustion engine, and an actual lambda value, which occurs at the output of a controlled system as a function of the injection calculation, is returned to the controller. At least one system parameter of the controlled system is determined, and the determined system parameter is transferred to a Smith predictor added to the controller for compensating the influence of the system dead time on the control loop characteristics.

Abstract: An internal combustion engine has a plurality of cylinders and an exhaust tract into which a mixture which is situated in the respective cylinder is introduced in the respective discharge strokes. A combustion misfire rate is determined as a function of at least one operating variable of the internal combustion engine. A temperature in the exhaust tract is determined as a function of the combustion misfire rate.

Abstract: A control apparatus which can improve the accuracy of control of a controlled variable by a control input exhibiting a periodic fluctuating behavior. The control apparatus calculates an air-fuel ratio correction value DKCMD such that the output from an oxygen concentration sensor converges to a target output, and calculate a modulated value DKCMD_DSM by modulating DKCMD with an algorithm to which is applied a ? ? modulation algorithm. Further, the control apparatus calculates a reference air-fuel ratio KCMDBS according to an exhaust gas volume, calculates a model modification coefficient KTRQFF using a modification coefficient calculated such that DKCMD become equal to 0, calculates an adaptive reference air-fuel ratio KCMDADP by the equation of KCMDADP=KCMDBS×KTRQFF, and calculates a target air-fuel ratio KCMD by the equation of KCMD=KCMADP+DKCMD_DSM.

Abstract: A prediction based engine control system is disclosed. The engine control system may have sensor configured to sense a current engine operation and generate a corresponding signal and a controller in communication with the sensor. The controller may be configured to receive the signal, compare the current engine operation to an allowable range of engine operation, predict a future engine operation based on the signal, and limit current engine operation based on the prediction, even when the current engine operation is within the allowable range of operation.

Abstract: An engine control system includes an oxygen (O2) sensor diagnostic module that diagnoses an O2 sensor and requests a minimum air per cylinder (APC). A throttle actuator module controls a throttle to adjust a mass air flow based on the minimum APC.

Abstract: A method for operating an internal combustion engine having a combustion method with homogeneous auto ignition. A driver's demand, predetermined by the gas pedal, is converted into a desired torque to be given off by the engine. A reference charge value for the air charge is determined by a working-point-dependent lambda value (?opt) that can be predetermined. Based on this, a throttle valve position is set. Parallel to this, a desired torque is calculated for the fuel path with a reference lambda value, and an actual charge is calculated to yield a fuel amount to be injected. The reference lambda value results from an optimal lambda value for the mode of operation of homogeneous compression ignition, as long as the lambda value is within the rich and lean limits, respectively, of the combustion method of homogeneous compression ignition. The fuel mass is varied within the rich and lean limits to compensate dynamic processes.

Abstract: Air/fuel imbalance monitoring systems and methods for monitoring air/fuel ratio imbalance of an internal combustion engine are disclosed. In one embodiment, an oxygen sensor is sampled above cylinder firing frequency and a ratio of data from at least one window over a total number of windows is determined. The approach can be used to indicate imbalances between engine cylinders.

Abstract: Various systems and methods are described for controlling an engine in a vehicle in response to an equilibrium value of an exhaust gas constituent generated from an exhaust gas sensor. One example method comprises during engine fueling below a threshold amount where at least one intake valve and one exhaust valve of the engine are operating: generating an equilibrium value of an exhaust gas constituent reading of the exhaust gas sensor, the equilibrium value based on a trajectory of the exhaust gas constituent reading, and under selected engine combusting conditions, adjusting the sensor signal based on the equilibrium value.

Abstract: A method and system for estimating CO2 produced by an internal combustion engine disposed in a vehicle and transmitting the CO2 produced to a display device within the vehicle are disclosed. Estimated CO2 produced is based on amount of fuel consumed and fuel composition, e.g., alcohol content in a gasoline-alcohol blend. The amount of fuel consumed is computed based on fuel pulse width commanded to fuel injectors disposed in the engine, the pressure drop across the fuel injectors, and fuel injector nozzle cross-section. Instantaneous CO2 produced and/or average CO2 produced can be computed and displayed. Instantaneous CO2 produced is averaged over a short interval with the display updated regularly. Average CO2 produced is averaged over a typically longer interval, being reset, in one embodiment, by an operator of the vehicle depressing a reset button.

Abstract: To avoid potentially erroneous results, monitoring the operation of an oxygen sensor of an internal combustion engine of a motor vehicle to detect a slow response of the oxygen sensor as indicative of an oxygen sensor fault is temporarily suspended in response to a brake operation transition of a braking system of the vehicle.

Abstract: An oxygen storage capacity (OSC) monitoring system for a vehicle having a catalytic converter includes an inlet oxygen sensor that generates an inlet sensor signal (ISS) based on an oxygen content of exhaust flowing into the catalytic converter. A control module receives the ISS, increases a closed loop fuel control gain during a first period and determines a fuel control factor based on the ISS during the first period. The control module determines an OSC when an average value of the fuel control factor is greater than a first value and is less than a second value during the first period.

Abstract: An intake air quantity correcting device calculates an intake air quantity as a sensing target of an airflow meter (an intake air quantity sensor) based on an injection quantity sensing value sensed with a fuel pressure sensor (an injection quantity sensor) and an oxygen concentration sensing value sensed with an A/F sensor (an oxygen concentration sensor). The intake air quantity correcting device regards a difference between the intake air quantity calculation value calculated in this way and an intake air quantity sensing value sensed with the airflow meter as a sensing error of the airflow meter and corrects the intake air quantity sensing value of the airflow meter based on the sensing error.

Abstract: An engine exhaust treatment system using a control system is described. In one form of the present invention, engine exhaust gas contaminates are passed through a selective reduction catalyst and a contaminate reducing agent is injected into the catalyst. The amount of contaminates present in the exhaust proximate to the selective reduction catalyst are sensed using at least one sensor. In one embodiment, input signals are sent to a control system from the sensor or sensors and a feedforward control combined with a feedback loop is used to transform these signals and a predetermined catalyst output contaminate value into an output signal. The output signal instructs a provider to inject contaminate reducing agents in a manner to efficiently track the desired predetermined catalyst output contaminate value.

Abstract: Internal combustion engine air-fuel ratio control apparatus and method in which the target air-fuel ratio of exhaust gas flowing into an exhaust-gas purification catalyst unit is controlled through at least proportional-integral control such that the correction amount per unit time of the oxygen amount in said catalyst unit is maintained constant. When the intake air amount is smaller than a predetermined amount and the air-fuel ratio detected by an oxygen sensor provided downstream of the catalyst unit is rich, the target air-fuel ratio is controlled to suppress an increase in the air-fuel ratio in the exhaust-gas purification catalyst unit. Accordingly, even if rapid acceleration operation is performed in a state where the intake air amount is extremely small and the air-fuel ratio detected by the oxygen sensor is rich, NOx in exhaust gas can be sufficiently removed through reduction reactions at the exhaust-gas purification catalyst unit.

Abstract: An engine control system includes a unit which outputs a command for changing an air-fuel ratio of an exhaust gas, a unit which computes an in-cylinder oxygen concentration, a memory which stores a first value and a second value of parameters (ignition timing, injection pressure, pilot injection quantity). The first value is set in a case that the in-cylinder oxygen concentration is a first oxygen concentration. The second value is set in a case that the in-cylinder oxygen concentration is a second oxygen concentration which is higher than the first oxygen concentration. The values of the parameters are set in such a manner as to correlate to the in-cylinder oxygen concentration of during a transition period of the air-fuel ratio. The values of the parameters are obtained by an interpolation based on the first and the second value of the parameter and the in-cylinder oxygen concentration.

Abstract: This invention aims at providing a fuel admission control unit to control a diesel engine, with which ensuring compatibility between the exhaust gas performance and the engine speed response performance is achieved by a simple control with a consideration of the residual oxygen in the EGR gas.

Abstract: A fuel injection control apparatus for a multi-fuel engine can optimize a fuel injection quantity, using only one basic injection map, irrespective of alcohol concentration of a fuel. An E-concentration determining apparatus determines alcohol concentration of a fuel, based on a measured oxygen amount in exhaust. Basic injection quantities are stored in a basic injection map. E-concentration coefficients are stored in an E-concentration coefficient table for a plurality of alcohol concentrations in the fuel. A basic injection quantity, corresponding to a current rotary engine speed and a throttle opening, is selected from the basic injection map. A concentration coefficient, corresponding to the alcohol concentration and the basic injection quantity, is selected from the E-concentration coefficient table. A fuel injection quantity calculator determines an applied fuel injection quantity by multiplying the basic injection quantity by the concentration coefficient.

Abstract: A method of measuring an initial hydrocarbon concentration in a canister includes opening a purge control valve thereby introducing hydrocarbons from the canister to a cylinder; calculating an amount of air introduced into the cylinder; and calculating the initial hydrocarbon concentration based on the amount of air. A method of controlling fuel injection includes measuring an initial hydrocarbon concentration in a canister by opening a purge control valve in a fuel cut-off mode; determining a driving state of a vehicle; calculating an air inflow to a cylinder according to the driving state of the vehicle; calculating a ? set-point according to the driving state of the vehicle; and calculating fuel injection amount based on the air inflow and the ? set-point. Also, a system for controlling fuel injection.

Abstract: A control device of an internal combustion engine calculates ignition delays in lean combustion and rich combustion, standardizes the ignition delays based on ignition timing, and further standardizes the ignition delays based on injection quantity and injection timing of pilot injection respectively. The control device calculates a present ignition delay by linear interpolation of the standardized ignition delays in the lean combustion and the rich combustion. Moreover, the control device corrects the present ignition delay with the ignition timing and further corrects the present ignition delay with the injection quantity and the injection timing of the pilot injection. The control device calculates a command value of the injection timing by subtracting the corrected present ignition delay from target ignition timing.

Abstract: A control input (DUT) for controlling a heater (13) which heats an active element (10) of an exhaust gas sensor (8) includes at least one of another component depending on the difference between temperature data of the active element (10) and a target temperature, a component depending on the target temperature, and a component depending on the temperature data of the active element (10). The control input is determined by an optimum control algorithm. A component depending on the temperature of an exhaust gas and the component depending on the target temperature are determined based on a predictive control algorithm. The temperature of the active element (10) of the exhaust gas sensor (8) is thus controlled stably at a desired temperature.

Abstract: A diagnostic system for an engine includes an oxygen detection module, a timing module and a control module. The oxygen detection module receives an oxygen signal from an oxygen sensor that detects an oxygen level in an exhaust system of the engine. The oxygen signal has N rich states and M lean states, where N and M are integers greater than or equal to 1. The timing module determines a rich period that the oxygen signal is in at least one of the N rich states and determines a lean period that the oxygen signal is in at least one of the M lean states. The control module detects an asymmetrical error with the oxygen sensor based on a comparison between the rich period and the lean period.

Abstract: A device, which detects information about a hydrogen concentration level, includes an air-fuel ratio sensor, an air-fuel ratio controller, and a detecting portion. The detecting portion calculates either a ratio of response periods or a difference between the response periods to detect the hydrogen concentration level. One of the response periods is a period from the time the air-fuel ratio controller switches the target air-fuel ratio from rich to lean to the time the air-fuel ratio sensor detects this. The other of the response periods is a period from the time the air-fuel ratio controller switches the target air-fuel ratio from lean to rich to the time the air-fuel ratio sensor detects this. This allows the decisions of a variation between cylinders and an exhaust purifying catalyst degradation.

Abstract: The invention concerns a method for determining the composition of a fuel mixture from a first and at least a second fuel for operating a combustion engine, whereby the fuel mixtures of different compositions require various air/fuel ratios to achieve a stoichiometric combustion. Thereby it is provided that the air volume that has been delivered to the combustion engine, the fuel quantity that has been delivered and the oxygen content in the exhaust gas of the combustion engine are determined during one or several stationary operating phases of the combustion engine during one or several measuring phases, and in that the composition of the fuel mixture is determined from these values. The procedure allows an accurate and reliable determination of the composition of a fuel mixture for combustion engines that are operated in flex-fuel-mode.

Abstract: An exhaust gas recirculation device of an internal combustion engine (1) including a low-pressure EGR passage (20), a high-pressure EGR passage (21), a low-pressure EGR valve (23) and a high-pressure EGR valve (24) further includes an air-fuel ratio sensor (12) that is disposed in the exhaust passage (4) upstream of the position of its connection with the low-pressure EGR passage (20). In the case where a predetermined fuel-cut condition is satisfied, an ECU (30) estimates the flow amounts of exhaust gas flowing in the low-pressure EGR passage (20) and the high-pressure EGR passage (21), on the basis of the oxygen concentrations acquired by the air-fuel ratio sensor (12) at timings at which the exhaust gases recirculated into the intake passage (3) via the low-pressure EGR passage (20) and via the high-pressure EGR passage (21) reach the air-fuel ratio sensor (12), respectively.

Abstract: A method and system are provided for controlling a throttle valve and an EGR valve in internal combustion engine. The method includes, but is not limited to the steps of measuring an actual fresh mass air flow value entering the engine, determining an exhaust oxygen concentration set point ([O2]spEM) indicative of the oxygen concentration in the exhaust manifold, calculating an air reference value (Airreference) as a function of the exhaust oxygen concentration set point ([O2]spEM) and determining an oxygen concentration feedback value ([O2]fdIM, [O2]fdEM) representative of the oxygen concentration in the engine. The method further includes, but is not limited to the steps of obtaining a position information for the throttvalve by by comparing the actual fresh mass air flow value and air reference value (Airreference) and obtaining a position information for the EGR valve by comparing the oxygen concentration feedback value ([O2]fdIM, [O2]fdEM) and oxygen concentration set point ([O2]spEM).

Abstract: In a diagnosis apparatus for an internal combustion engine which determines the abnormality of a linear A/F sensor which is disposed on the upstream side of a catalyst of the engine and detects the A/F of exhaust gas, the apparatus includes a response/gain deterioration detection unit that separately detects the response deterioration in which the response of the linear A/F sensor is delayed and the gain deterioration in which the detection sensitivity of the linear A/F sensor is abnormal.

Abstract: In an abnormality diagnostic device and an abnormality diagnostic device for an air-fuel ratio sensor that detects the air-fuel ratio of exhaust gas of an internal combustion engine, a system extending from a fuel injection valve to the air-fuel ratio sensor is model by a first order response delay, and a parameter in the first order response delay is identified based on an input air-fuel ratio that is given to the air-fuel ratio sensor and an output air-fuel ratio that is output from the air-fuel ratio sensor. Then, the presence/absence of abnormality regarding a predetermined characteristic of the air-fuel ratio sensor is determined based on the parameter identified. Thus, abnormality is diagnosed regarding individual characteristics of the air-fuel ratio sensor.

Abstract: An ECU controls an A/F sensor that is provided in an exhaust system of an internal combustion engine and produces current outputs corresponding to the concentration of oxygen in exhaust gas by being supplied with voltage and produces voltage outputs corresponding to the concentration of oxygen in exhaust gas according to the difference between the oxygen concentration around one of a pair of electrodes of the A/F sensor and the oxygen concentration around the other electrode. The ECU has: an energization limitation portion that, when moisture content is adhering on an inner face of an exhaust passage near the A/F sensor, energizes a heater of the A/F sensor while limiting the amount of power supplied thereto; and a specific output obtaining portion that obtains voltage outputs from the A/F sensor at least when the energization limitation portion is energizing the heater while limiting the amount of power supplied thereto.

Abstract: A direct injection spark ignition multi-cylinder internal combustion engine operative in a controlled auto-ignition combustion mode includes a direct fuel injection system, a spark ignition system and a controllable engine valve system. The air/fuel ratio in the exhaust gas feedstream and an intake mass air flow are measured and an actual air/fuel ratio is calculated based upon the intake mass air flow and engine fueling. Magnitude of a negative valve overlap period between an exhaust valve closing and an intake valve opening is adjusted based upon the measured mass air flow. Timing of pre-injection fueling is adjusted during the negative valve overlap period based upon the measured air/fuel ratio.

Abstract: A system extending from a fuel injection valve to an air-fuel ratio sensor is modeled by using a first order response delay element. Parameters of the first order response delay element T, k are identified based on an input u(t) based on an input air-fuel ratio that occurs when the input air-fuel ratio is relatively sharply changed in accordance with an engine operation requirement, and an output y(t) of the air-fuel ratio sensor that changes in response to a change in the input air-fuel ratio. Then, an abnormality of characteristics (response rate and output) of the air-fuel ratio sensor is determined based on the identified parameter.

Abstract: An abnormality diagnostic device for an air-fuel ratio sensor that detects the air-fuel ratio of exhaust gas of an internal combustion engine is provided. The abnormality diagnostic device includes: a device that an device that models a system extending from a fuel injection valve to the air-fuel ratio sensor by using a first order response delay element and a waste time element, and that identifies at least a waste time of the waste time element based on an input given to the air-fuel ratio sensor and an output obtained from the air-fuel ratio sensor; and another device that performs determination about an abnormality of the waste time based on the identified waste time.

Abstract: In a NOx purification system 1 provided with a NOx occlusion reduction catalyst 20 and a control unit 30 which executes a NOx regeneration control and a sulfur poisoning regeneration control, a binary ? sensor 26 and a reducing agent concentration sensor 25 for detecting a concentration of the reducing agent are disposed downstream of the NOx occlusion reduction catalyst 20. The level of deterioration of the NOx occlusion reduction catalyst 20 caused by sulfur poisoning is estimated on the basis of a time period Ta from a time point T3 at which a marked decrease of oxygen concentration is detected by the binary ? sensor 26 to the time point T2 at which the marked increase of the oxygen concentration is detected by the reducing agent concentration sensor 25 under the NOx regeneration control.

Abstract: An engine control module includes an exhaust heating module, a temperature determination module, and a resistance measuring module. The exhaust heating module operates an engine at a predetermined speed to generate an exhaust gas having a predetermined temperature. The exhaust gas heats a heating element of an oxygen sensor. The temperature determination module determines, based on the predetermined speed, when the heating element is heated to the predetermined temperature. The resistance measuring module determines a resistance of the heating element when the heating element is heated to the predetermined temperature.

Abstract: An electronic control unit 50 determines whether the ambient air in the vicinity of an oxygen concentration sensor 55 in an exhaust passage 30 has become equal to the atmospheric state as a fuel cut-off operation is executed. If the ambient air in the vicinity of the oxygen concentration sensor 55 is equal to the atmospheric state, the electronic control unit 50 executes a learning process, in which a detection value C of the oxygen concentration sensor 55 is stored as a learned value Cstd in a memory 56. The electronic control unit 50 continues the learning process until a predetermined time period set based on an exhaust gas transport delay elapses from when the fuel cut-off operation is terminated.

Abstract: A fuel injection control device for a multi-fuel engine includes a corrector and a reviewer. An alcohol concentration learning unit is provided to learn an alcohol concentration in an injected fuel based on an oxygen concentration detected in an exhaust gas. A fuel injection amount controller is provided to control a fuel injection amount based on a learning value corresponding to the oxygen concentration. The corrector is configured to reduce the fuel injection amount corresponding to the learning value for a predetermined time period when the learning value is higher than a threshold value when an engine is started. The reviewer is configured to review the learning value to provide a revised learning value based on the oxygen concentration while the corrector reduces the fuel injection amount. The fuel injection amount is controlled based on the revised learning value after the corrector reduces the fuel injection amount.

Abstract: A method is for adjusting a fuel/air ratio by means of an on-off controller as well as a diagnostic method in which a desired fuel/air mixture is regulated in accordance with a test signal of a lambda probe that is embodied as a jump probe. The switching point of the on-off controller is moved/adapted while the oscillation of the test signal of the lambda probe is analyzed regarding the amplitude and/or the asymmetry of the oscillation around the switching point at a constant control stroke. A desired value for the asymmetry or the amplitude of the oscillation of the test signal of the lambda probe around the respective switching point is predefined, the switching point of the on-off controller being moved such that the desired value is reached.

Abstract: In an automobile fuel control system having an EGO sensor which sends voltage to an ECM in order to adjust fuel/air ratio, the EGO sensor being disabled and replaced with a substitute signal generator circuit which stimulates the ECM toward lean-running.

Abstract: The apparatus obtains a decreasing gradient of the maximum oxygen storing quantity Cmax with respect to the increase in an air flow rate Ga on the basis of two maximum oxygen storing quantities Cmax, which are respectively estimated in case where the air flow rate Ga assumes two different values, and the two values of the air flow rate Ga. As the deterioration degree of the catalyst unit 53 increases, the decreasing gradient increases. When the deterioration degree of the catalyst unit 53 is the same, the decreasing gradient tends to be the same, even if the degree of the response of the change in the output from a downstream air-fuel-ratio sensor 67 varies. Accordingly, the obtained decreasing gradient can be a value correctly indicating the deterioration degree of the catalyst unit 53.

Abstract: A controller is provided for directing control of a process performed to control an amount of a pollutant emitted into the air. The process has multiple process parameters (MPPs) The controller includes either a neural network process model or a non-neural network process model. Whichever type model is included, it will represent a relationship between one of the MPPs and other of the MPPs. The controller also includes a control processor having the logic to determine the validity of a measured value of the one MPP based on the one model. The control processor directs control of the process in accordance with the measured value of the one MPP only if the measured value of the one MPP is determined to be valid. On the other hand, if the measured value is determined to be invalid, the control processor may direct control of the process in accordance with an estimated value of the one MPP.

Abstract: A catalyst deterioration determination device for determining deterioration of an exhaust gas purging catalyst arranged in an exhaust passage of an internal combustion engine is disclosed. The determination device forcibly changes an air-fuel ratio of an air-fuel mixture, calculates an oxygen occlusion amount of the catalyst based on an oxygen concentration of the exhaust gas at a downstream side of the catalyst that varies after the forcible changing of the air-fuel ratio, and performs deterioration determination on the catalyst based on the calculated oxygen occlusion amount. The engine includes a function for performing increasing correction on a fuel injection amount so that the air-fuel ratio of the air-fuel mixture becomes richer than the stoichometric air-fuel ratio.

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: A method and system are disclosed for compensating a mass air flow signal produced by a mass air flow sensor in fluid communication with an air intake passageway of an internal combustion engine. A mass air flow signal produced by the mass air flow sensor is monitored and an expected oxygen concentration of exhaust gas produced by the engine is determined. A compensation parameter is determined as a function of the expected oxygen concentration and a measured value of the oxygen concentration of the exhaust gas. A compensated mass air flow value is determined as a function of the mass air flow signal and the compensation parameter.

Abstract: The air-fuel-ratio control apparatus for an internal combustion engine obtains a composite air-fuel ratio abyfs from a downstream-side correction value Vafsfb(k) based upon an output value Voxs from a downstream air-fuel-ratio sensor 67 and an output value Vabyfs from an upstream air-fuel-ratio sensor 66, and obtains an upstream-side feedback correction value DFi on the basis of the composite air-fuel ratio abyfs. A fuel injection quantity Fi is determined to a value obtained by adding the upstream-side correction value DFi to a control-use base fuel injection quantity Fbasec (=base fuel injection quantity Fbase·coefficient Ksub).

Abstract: A monitoring method and a monitoring arrangement, wherein: (a) first comparison value is established based on information from a sensor as to the measured magnitude of a parameter related to exhaust gases flowing out of an exhaust gas aftertreatment appliance included in an exhaust aftertreatment system; b) a second comparison value corresponding to the first comparison value is established based on a value representing the magnitude of said parameter calculated on the basis of a calculation model; c) a difference value representing the difference between said comparison values is established; d) steps a)-c) are repeated during a certain period of time and a variance value representing the variance of the difference value during this period of time is established; and e) the variance value is compared with a given threshold value for generation of information regarding the functioning of the sensor or the system.