Abstract: An engine system includes an exhaust system fluidly connected to an electronically controlled engine. Exhaust from the engine may travel a first pathway through a turbine of a turbocharger, or a second pathway that bypasses the turbine. An electronically controlled wastegate vale is biased to close the second pathway. An electronic controller is in communication with the electronically controlled engine and the electronically controlled wastegate valve. The electronic controller is configured to execute a wastegate diagnostic algorithm to detect a stuck closed default condition of the electronically controlled wastegate valve, and derate the engine in response to detection of a stuck closed fault condition.

Abstract: A control device for a hybrid vehicle causes the hybrid vehicle to travel in limp-home mode with motive power from an engine when either a motor or a battery for travel cannot be used. The engine incorporated in the hybrid vehicle includes an EGR device for recirculating part of exhaust gas to an intake system of the engine again. Even if an operation state of the engine satisfies a prescribed EGR permission condition for operating the EGR device, during the travel in limp-home mode with an abnormality detection flag being set to 1, the control device prohibits operation of the EGR device.

Abstract: An exhaust gas purification system including an exhaust gas passageway which routes a flow of exhaust gas from an exhaust gas source to an intake manifold; an exhaust gas passageway valve which controls flow to the intake manifold; a cooling system coupled with the exhaust passageway positioned at a location upstream of the exhaust gas source and downstream of the intake manifold and operable to transfer heat from the flow of exhaust gas to a coolant in flow communication with the cooling system; a bypass passageway coupled with the exhaust gas passageway and bypassing the cooling system; a bypass valve operable to control flow through the bypass passageway; at least one valve operation sensor; and a controller operable to control the bypass valve to direct the flow of exhaust gas to the bypass passageway during exhaust gas recirculation based on a signal from the valve operation sensor.

Abstract: An object of the present invention is to suppress the dispersion of EGR gas amount between cylinders when the stuck open state arises in an EGR valve in an EGR apparatus for an internal combustion engine in which an EGR passage is branched on an intake system side into a plurality of EGR branch pipes, and the respective EGR branch pipes are connected respectively to intake branch pipes provided for the respective cylinders. In the present invention, if the EGR valve is stuck open, the exhaust pressure is reduced in an exhaust system of the internal combustion engine, while suppressing an amount of decrease in a driving force of a vehicle which carries the internal combustion engine within an allowable range.

Abstract: A method includes detecting a presence of a fouling layer in an exhaust gas recirculation cooler of an internal combustion engine. The flow of a coolant through the exhaust gas recirculation cooler is stopped for a predetermined period of time while the engine exhaust gas flows through the exhaust gas recirculation cooler. The flow of an engine exhaust gas exiting from the exhaust gas recirculation cooler is diverted to at least one of a turbine of a turbocharger, and an exhaust pipe of the internal combustion engine. The fouling layer from the exhaust gas recirculation cooler is expelled along with the engine exhaust gas exiting the exhaust gas recirculation cooler.

Abstract: An EGR system control method of an engine may include calculating a target mass flux ({dot over (m)}egrd) of EGR gas flowing an EGR line, calculating an effective flowing area (EFA) of an EGR valve disposed on the EGR line, calculating an EGR flow sensitivity by dividing the target mass flux with the effective flowing area, and controlling a real opening rate of the EGR valve by applying the EGR flow sensitivity to a target opening rate of the EGR valve. Accordingly, a gain value is varied on a real time according to an effective flowing area of the EGR valve and a target mass flux of EGR gas such that real opening rate of an EGR valve is accurately and precisely controlled.

Abstract: When a valve body is rotated toward a full-close position in a valve-close mode, a control portion controls an electric motor so that the rotating speed of the valve body is lower than that in a valve-open mode. A rotating speed of the valve body around the shaft in the valve-close mode is lower than that in the valve-open mode. Thus, when the seal ring is brought into contact with the inner wall surface, an impact generated therebetween can be moderated. While the valve body is rotated toward the full-close position, a seal ring is gradually elastically deformed. A sliding friction between the seal ring and the inner wall surface can be reduced.

Abstract: Various systems and methods are described for operating an engine system having a sensor coupled to an exhaust gas recirculation system in a motor vehicle. One example method comprises during a first operating condition, directing at least some exhaust gas from an exhaust of the engine through the exhaust gas recirculation system and past the sensor to an intake of the engine and, during a second operating condition, directing at least some fresh air through the exhaust gas recirculation system and past the sensor.

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: In an internal combustion engine with separate cylinder banks, separate exhaust passages are connected to each cylinder bank of an engine and a shared intake passage is connected to both cylinder banks. One end of an EGR passage is connected to the separate exhaust passage of one cylinder bank, and the other end of the EGR is connected to the shared intake passage. If it is determined that an EGR valve in the EGR passage is stuck in an open state, a fuel-cut control is executed in the cylinder bank that is connected to the separate exhaust passage to which the EGR passage is connected. Thus, even when the EGR valve is stuck in an open state, it is possible to prevent the internal combustion engine from operating unstably.

Abstract: A method for adjusting an exhaust gas recycling rate in an internal combustion engine exhaust gas recycling system, comprising: arranging the exhaust gas recycling system in at least one of a fresh gas line, an exhaust gas line, and an exhaust gas recycling line of the internal combustion engine; actuating at least one additional valve; adjusting the at least one additional valve temporarily by changing the operation of the internal combustion engine based on an exhaust gas rate associated with a current operating point of the internal combustion engine; diagnosing the at least one additional valve; and evaluating the change of at least one engine operating parameter dependent on the exhaust gas recycling rate.

Abstract: A system for diagnosing a switchable roller finger follower (SRFF) and an oil control valve (OCV) includes a signal monitoring module and a fault detection module. The signal monitoring module receives at least one of an individual cylinder fuel correction (ICFC) signal and an air/fuel ratio imbalance (AFIM) signal when: an engine speed signal is within a predetermined range of speed; an engine load signal is within a predetermined range of load; and a charcoal canister vapor signal is within a predetermined range of flow rate. The fault detection module detects a fault of at least one of a SRFF and an OCV based on an exhaust gas recirculation value and at least one of the ICFC and AFIM signals. The ICFC and AFIM signals are generated based on: an engine position signal; and at least one of an oxygen signal and a wide range air fuel signal.

Abstract: A method to operate an electronic controlled internal combustion engine to perform on board NOx emissions level diagnostics. In one embodiment, the method may include operating the engine to maintain a predetermined temperature for a predetermined period of time, determining whether the engine operating status is stable for one of cruise control, idle engine speed, engine torque, or high idle regeneration for a predetermined period of time, cycling the EGR valve between a first position for a predetermined period of time and then in a second position for a predetermined period of time, a determining a change in engine out NOx levels to determine whether an engine component or system is malfunctioning.

Abstract: The disclosure relates to a method for the measurement of relative air humidity in a fresh air induction tube of an internal combustion engine. Here a concentration of oxygen in the fresh air induction tube is measured by an oxygen sensor and a temperature in the fresh air induction tube is determined. The relative air humidity is determined depending on the measured concentration of oxygen and the determined temperature.

Abstract: A control system (36) for comparing engine speed data to an engine speed threshold above which the engine is considered to be running (40), for comparing engine temperature data to an engine temperature threshold (60), and once engine speed data has become greater than the engine speed threshold, for causing engine torque to be limited to an engine torque limit until the first to occur of: engine temperature data exceeding the engine temperature threshold, a first timer (44), started upon engine speed data having become greater than the engine speed threshold, having timed to a time that is a function of engine temperature data, and a second timer (54), started upon engine speed data having become greater than the engine speed threshold and engine oil pressure data having become greater than an engine oil pressure threshold, having timed to a time that is also a function of engine temperature data.

Abstract: When an abnormality determining process is cancelled when a fuel cut is stopped, an EGR valve (33), which is open wider than normal from the process, is returned to its original opening amount (i.e., fully closed), and fuel injection in an engine (1) is resumed. However, during execution of the abnormality determining process, an EGR passage (32) is full of air. Also, when the EGR valve (33) is returned to the fully closed state, there is a response delay in the change in the flowrate of air that flows from the EGR passage (32) into the air passage (4) following that return, such that excess air flows into the air passage (4). As a result, the intake air amount of the engine (1) becomes excessive for the fuel injection quantity after fuel injection resumes. The fuel injection quantity is thus increase corrected to inhibit this from happening.

Abstract: An internal combustion engine is equipped with an EGR system that includes an EGR heat exchanger. A method for monitoring the EGR heat exchanger includes monitoring an EGR gas inlet temperature to the EGR heat exchanger, an EGR gas outlet temperature from the EGR heat exchanger, a coolant temperature and a mass EGR flowrate through the EGR heat exchanger for a present engine operating point. An actual thermal effectiveness of the EGR heat exchanger for the present engine operating point is determined. A maximum heat transfer coefficient for the EGR side of the EGR heat exchanger is determined for the present engine operating point. The EGR heat exchanger is regenerated when the actual heat transfer coefficient differs from the maximum heat transfer coefficient for the present engine operating point.

Abstract: A method for controlling an exhaust gas recovery system for an engine includes generating a signal to control exhaust gas flow through an exhaust gas heat exchanger, and generating a diagnostic code based on a difference between coolant temperature downstream of the exhaust gas heat exchanger and coolant temperature downstream of the engine. A vehicle has an engine, and an exhaust heat recovery system with an exhaust gas heat exchanger, a first temperature sensor downstream of the engine, and a second temperature sensor downstream of the exhaust gas heat exchanger. A controller for the vehicle is configured to: (i) generate a signal to control exhaust gas flow through the exhaust gas heat exchanger, and (ii) generate a diagnostic code based on a difference between coolant temperature measured by the first and second temperature sensors.

Abstract: In the engine including an MPL-EGR system having an HPL-EGR mechanism 6 and an LPL-EGR mechanism 7, a pressure difference between upstream side pressure and downstream side pressure of a low pressure EGR cooler 73 provided in the LPL-EGR mechanism 7 is detected by a pressure difference sensor 89. When an actual pressure difference value detected is higher than a reference pressure difference value in a state where no blocking occurs in the LPL-EGR mechanism 7, and the deviation amount therebetween reaches a predetermined amount, it is determined that the blocking occurs in the inside of the low pressure EGR cooler 73. In contrast, when the actual pressure difference value detected is lower than the reference pressure difference value, and the deviation amount therebetween reaches a predetermined amount, it is determined that the blocking occurs in the inside of the pipe members 74 and 75 except the low pressure EGR cooler 73.

Abstract: While an engine is at idling state with an EGR valve fully closed, an EGRLQ is detected or estimated. When the EGRLQ exceeds a specified threshold, a target intake manifold pressure is established so that the EGRLQ becomes less than the specified value and an IAFRI-control is executed so that the intake manifold pressure becomes the target pressure. An intake air flow rate QIN can be increased and a differential pressure DP between upstream and downstream of the EGR valve 31 is reduced to effectively decrease an EGR rate. An ignition timing is retarded according to an increase in intake air flow rate QIN due to the IAFRI-control. An increase in torque (increase in intake air flow rate) due to the IAFRI-control is canceled by an increase in a required torque (increase in required intake air flow rate) due to a retard of the ignition timing.

Abstract: An exhaust gas recirculation system including an exhaust gas passageway which routes a flow of exhaust gas from an exhaust gas source to an intake manifold; an exhaust gas passageway valve which controls flow to the intake manifold; a cooling system coupled with the exhaust gas passageway positioned at a location upstream of the exhaust gas source and downstream of the intake manifold and operable to transfer heat from the flow of exhaust gas to a coolant in flow communication with the cooling system; a bypass passageway coupled with the exhaust gas passageway and bypassing the cooling system; a bypass valve operable to control flow through the bypass passageway; at least one valve operation sensor; and a controller operable to control the bypass valve to direct the flow of exhaust gas to the bypass passageway during exhaust gas recirculation based on a signal from the valve operation sensor.

Abstract: A method to operate an electronic controlled internal combustion engine to perform on board NOx emissions level diagnostics. In one embodiment, the method may include operating the engine to maintain a predetermined temperature for a predetermined period of time, determining whether the engine operating status is stable for one of cruise control, idle engine speed, engine torque, or high idle regeneration for a predetermined period of time, cycling the EGR valve between a first position for a predetermined period of time and then in a second position for a predetermined period of time, a determining a change in engine out NOx levels to determine whether an engine component or system is malfunctioning.

Abstract: An abnormality diagnosis device for an exhaust gas recirculation device in an internal combustion engine is provided. The exhaust gas recirculation device has an exhaust gas recirculation valve that adjusts the amount of recirculation exhausts gas returned from an exhaust passage to an intake passage of the engine. The abnormality diagnosis device includes a control section that changes the exhaust gas recirculation valve to diagnose an abnormality in the exhaust gas recirculation device. When the abnormality diagnosis execution condition is met, the control section, prior to the execution of the valve closing operation, inhibits the opening degree adjustment and executes a valve opening process to increase the opening degree of the valve from the opening degree at the time to a second target opening degree greater than the first target opening degree.

Abstract: A method is provided for the diagnosis of the EGR cooler efficiency in a Diesel engine that includes but is not limited to construction of a model for determining the temperature drop y=?T in the EGR cooler, the model having a parameter vector ? and an input vector x; performing a model calibration phase in order to estimate the bias h0 of the system; calculation of a set of primary residuals ?(?0, x, ?T), staffing from the model equation and using the results of the calibration phase; calculation of a set of improved residuals ?N(?0): ? N ? ( ? 0 ) = 1 N ? ? k = 1 N ? ( ? ? ( ? 0 , x k , y k ) - h 0 ) where N is the number of samples on which the diagnostic test is performed; calculation of a diagnostic index S: S=?TNR0?1?N and, use of the diagnostic index S in order to diagnose the efficiency of the EGR cooler.

Abstract: An internal combustion engine includes at least two cylinders, an intake duct, an exhaust gas section and an exhaust gas recirculation line. The cylinders include a combustion chamber. The intake duct communicates with the combustion chambers via a cylinder inlet channel of the intake duct depending upon a switch position of a gas inlet valve. The exhaust gas section communicates with the combustion chambers depending upon a switch position of at least one gas outlet valve. Exhaust gas is guided back to the inlet channels via the exhaust gas recirculation line dependent upon a switch position of the exhaust gas recirculation valve. To detect a mixing air temperature in the inlet channels, a mixing air temperature sensor is provided. The determined mixing air temperatures are compared. Exhaust gas guided back due to uneven distribution is identified if a difference between the determined mixing air temperature is greater than a predetermined threshold value.

Abstract: To accurately specify an EGR rate from an output value of an in-cylinder pressure sensor, a specifying method of an EGR rate in an internal combustion engine of the present invention acquires an output value of an in-cylinder pressure sensor at an intake stroke to calculate comparison data related to an in-cylinder pressure at the intake stroke from the acquired sensor output value. An output value of the in-cylinder pressure sensor at an exhaust stroke of the same cycle is also acquired to calculate comparison data related to the in-cylinder pressure at the exhaust stroke from the acquired sensor output value. Two comparison data are compared to specify the EGR rate of an air-fuel mixture provided for combustion from a difference between the values.

Abstract: A method for operating an EGR system in an Internal Combustion Engine (ICE) is provided. The EGR system includes an EGR valve for regulating an exhaust gas flow into an EGR cooler and a by-pass line for by-passing the EGR cooler. The method includes monitoring an index value indicative of a clogging condition of the EGR cooler, closing the exhaust gas flow in the EGR cooler if the index value exceeds a predefined threshold, and opening the exhaust gas flow in the EGR cooler if the index value is decreasing.

Abstract: An internal combustion engine includes an exhaust restriction valve and an exhaust gas recirculation control valve. Upon determining that a malfunction or fault condition exists relative to one of the valves, the controller may command the other valve to move towards a predetermined position. A malfunction or fault condition may result in derating of the engine.

Abstract: A determination is made more simply as to a malfunction of a low pressure EGR device that supplies an EGR gas from a low pressure EGR passage connecting between an exhaust passage at a location downstream of a turbine and an intake passage.

Abstract: A control system includes a throttle control module, an exhaust gas recirculation (EGR) control module, and a diagnostic control module. The throttle control module selectively maintains a desired throttle area when a vehicle is in a coastdown mode. The EGR control module opens an EGR valve when the desired throttle area is maintained. The diagnostic control module selectively diagnoses an error of an EGR system based on a pressure increase measured in an intake manifold of the vehicle when the EGR valve is open.

Abstract: An abnormality detection device for an exhaust gas recirculation apparatus is provided that can perform abnormality detection with respect to an EGR valve while suppressing the influence of a size relationship between an intake pressure and an exhaust pressure. An ECU (Electronic Control Unit) executes processing for extracting a pulse from an intake pipe pressure value. The ECU executes arithmetic processing for performing Fast Fourier Transform (FFT) with respect to an output waveform of an intake pressure sensor obtained by sampling processing, and also executes extraction processing that extracts a “frequency component corresponding to a period of an exhaust pulse”. The ECU executes processing that determines, in steps, whether or not the size of the extracted pulse (amplitude size) exceeds a threshold value. If the amplitude size exceeds the threshold value, the ECU executes processing that determines that a totally closed abnormality is occurring in the EGR valve.

Abstract: In a method for operating an internal combustion engine having exhaust gas recirculation, air is supplied to at least one combustion chamber via an intake manifold at least partially closable with the aid of a final control element, and a part of the exhaust gases flowing into an exhaust pipe is conducted via an EGR channel, which is at least partially closable with the aid of an EGR valve unit, into an area of the intake manifold, which lies between the final control element and the combustion chamber. A first variable, which characterizes the mass flow of the gas conducted through the EGR channel, is ascertained from a set of state variables of the internal combustion engine, which apply for an operating state in which the engine is in overrun operation and the final control element is essentially closed.

Abstract: A control method for an internal combustion engine including an exhaust gases post-processing system and a system for recirculating the exhaust gases towards the intake, wherein the engine can be switched from a regeneration operation mode with throttling to a nominal mode without throttling. At the end of the engine operation in the regeneration mode, the engine is temporarily operated in an intermediate mode with partial throttling for limiting the contrast of the intake noise.

Abstract: A failure diagnosis apparatus for an exhaust pressure sensor for detecting the exhaust pressure in an exhaust gas recirculation passage which connects an exhaust passage and an intake passage of an internal combustion engine. A first preliminary determination that the exhaust pressure sensor is normal, is made when the engine is in a predetermined low load operating condition and a difference between the detected exhaust pressure and the atmospheric pressure is equal to or less than a first determination threshold value. A second preliminary determination that the exhaust pressure sensor is normal, is made when the engine is in a predetermined high load operating condition and the difference between the exhaust pressure detected by the exhaust pressure sensor and the atmospheric pressure is equal to or greater than a second determination threshold value. A final determination that the exhaust pressure sensor is normal, is made when both of the first and second preliminary determinations are made.

Abstract: There is disclosed a method for diagnosing slow EGR response in an internal combustion engine equipped with an electronic controller with memory. In one embodiment, the method includes passing an EGR setpoint value and an actual EGR value through first order filters to eliminate high frequency noise; determining an actual EGR gradient as a function of any difference between the EGR set point and the actual EGR value while simultaneously determining an actual EGR gradient; and logging a fault in the electronic controller if the expected EGR gradient is greater than the actual EGR gradient by a predetermined amount.

Abstract: A method for operating an internal combustion engine Exhaust Gas Recirculation (EGR) system that includes producing an EGR valve position signal to decrease the amount of exhaust gas passed to the EGR cooler when a processor determines the EGR cooler efficiency is less than the predetermined level and producing an EGR coolant valve position signal to decrease the amount of coolant passed to the EGR cooler when such processor determines the EGR cooler efficiency is less than the predetermined level. The processor produced EGR valve and the EGR coolant valve position signals result in regeneration within the cooler, returning the effectiveness of the cooler to a near “clean” condition.

Abstract: A method and a device for operating an internal combustion engine having at least one mass flow line and a cooling device for cooling the mass flow in the mass flow line, as well as a bypass, having a bypass valve, that bypasses the cooling device. When the bypass valve is opened, the mass flow is conducted at least partly through the bypass. When the bypass valve is closed, the mass flow is conducted through the cooling device. Downstream from the cooling device and from the bypass in the mass flow line, a temperature of the mass flow in the mass flow line is determined. In at least one operating state of the internal combustion engine, a first temporal temperature gradient is determined with closed bypass valve. In the at least one operating state of the internal combustion engine, a second temporal temperature gradient is determined with closed position of the bypass valve.

Abstract: A valve control device performs control for eliminating or preventing fixation of an EGR valve (30) by opening/closing the valve near its fully closed position. After an engine stops, the valve control device performs “a fixation avoiding operation” for opening/closing EGR valve (30) near the fully closed position, and further, performs “a fixation determining operation”. When it is determined that the fixation of EGR valve (30) is eliminated, EGR valve (30) is positioned at the fully closed position, and a reference position is corrected such that the fully closed position is regarded as a reference position at which a valve opening/closing control is performed during the operation of the engine.

Abstract: An engine control, and in particular a method for controlling an engine including a low-pressure exhaust gas recycling loop. The method adjusts a predetermined engine operating parameter by controlling the position of an exhaust gas recycling valve, which is placed in the loop, for determining whether the predetermined measured quantity of the valve respects a predetermined criteria, and controls the position of an exhaust shutter, which is arranged outside the loop, when the quantity does not respect the criteria.

Abstract: An abnormality determination device for an EGR device, which is capable of determining the abnormality of the EGR device properly without interrupting the EGR operation. An ECU of an internal combustion engine detects an amount of fresh air drawn into a combustion chamber of the engine, carries out feedback control of the fresh air amount such that the detected fresh air amount converges to a predetermined target fresh air amount by controlling an opening of a throttle valve disposed in an intake system of the engine during execution of EGR by the EGR device. The ECU obtains a decreasing degree parameter which represent a degree of decrease in the fresh air amount caused by the feedback control, and determines abnormality of the EGR device based on the obtained decreasing degree parameter.

Abstract: In an internal combustion engine with separate cylinder banks, separate exhaust passages are connected to each cylinder bank of an engine and a shared intake passage is connected to both cylinder banks. One end of an EGR passage is connected to the separate exhaust passage of one cylinder bank, and the other end of the EGR is connected to the shared intake passage. If it is determined that an EGR valve in the EGR passage is stuck in an open state, a fuel-cut control is executed in the cylinder bank that is connected to the separate exhaust passage to which the EGR passage is connected. Thus, even when the EGR valve is stuck in an open state, it is possible to prevent the internal combustion engine from operating unstably.

Abstract: A low pressure EGR regulating valve is driven by an electric actuator, and an output of the electric actuator is transmitted to an intake air throttle valve through a link device. An ECU executes a failure determination to determine presence of a failure in a case where a sensed opening degree, which is sensed with a low pressure EGR opening degree sensor, is other than an opening degree that corresponds to a maximum opening degree of the throttle valve limited by a mechanical stopper. The ECU executes the failure determination after the energization of the electric actuator is stopped in response to stopping of the engine.

Abstract: A method for diagnosing slow EGR response in an internal combustion engine equipped with an electronic controller with memory, comprising: determining an actual EGR gradient; determining an expected EGR gradient comparing the expected EGR gradient to the actual EGR gradient determining the expected EGR gradient is greater that the actual EGR gradient and logging a fault in the electronic controller if the expected EGR gradient is greater than the actual EGR gradient, and optionally activating a warning to alert the operator of the logging event.

Abstract: A method for the diagnosis of an exhaust gas recirculation system in an internal combustion engine, including providing a pressure difference reading, which gives a pressure difference in an air supply section of the internal combustion engine or a pressure difference over the exhaust gas recirculation system; determining a pressure difference reference value as a function of one or more operating variables of the internal combustion engine; and detecting a fault in the exhaust gas recirculation system as a function of the pressure difference reading and of the pressure difference reference value.

Abstract: An EGR apparatus includes an EGR passage that connects an intake passage and an exhaust passage of an internal combustion engine in order to introduce a part of an exhaust gas into the intake passage, and an EGR valve for adjusting the amount of exhaust gas flowing through the passage. An oxygen concentration sensor that outputs a continuous value corresponding to the oxygen concentration of the exhaust gas flowing through the exhaust passage is provided in the exhaust passage. Valve-opening driving is performed on the EGR valve during fuel cut processing for halting the fuel supply of the internal combustion engine, and when a variation range of the output value of the oxygen concentration sensor accompanying the valve-opening driving is smaller than a predetermined value, it is determined that an abnormality is present in the EGR apparatus.

Abstract: The internal combustion engine has a valve driving mechanism (VM) capable of changing the valve-opening characteristic of at least one of an intake valve (Vi) and an exhaust valve (Ve), an in-cylinder pressure sensor for detecting the in-cylinder pressure in a combustion chamber and ECU. ECU calculates the variation amount of the in-cylinder pressure caused by the valve-overlap of the intake valve (Vi) and the exhaust valve (Ve), and based on this variation amount of the in-cylinder pressure and the in-cylinder pressure detected at a predetermined timing in the compression stroke, calculates an amount of air sucked in the combustion chamber, as well as, based on this calculated intake air amount, determines the ignition timing. The amount of air sucked in the combustion chamber is accurately and costlessly calculated, and the ignition timing is optimally determined by using the calculated air amount.

Abstract: An abnormality diagnosis device for an exhaust gas recirculation device in an internal combustion engine is provided. The exhaust gas recirculation device has an exhaust gas recirculation valve that adjusts the amount of recirculation exhausts gas returned from an exhaust passage to an intake passage of the engine. The abnormality diagnosis device includes a control section that changes the exhaust gas recirculation valve to diagnose an abnormality in the exhaust gas recirculation device. When the abnormality diagnosis execution condition is met, the control section, prior to the execution of the valve closing operation, inhibits the opening degree adjustment and executes a valve opening process to increase the opening degree of the valve from the opening degree at the time to a second target opening degree greater than the first target opening degree.

Abstract: A control system includes a throttle control module, an exhaust gas recirculation (EGR) control module, and a diagnostic control module. The throttle control module selectively maintains a desired throttle area when a vehicle is in a coastdown mode. The EGR control module opens an EGR valve when the desired throttle area is maintained. The diagnostic control module selectively diagnoses an error of an EGR system based on a pressure increase measured in an intake manifold of the vehicle when the EGR valve is open.

Abstract: The invention comprises a method and an article of manufacture to estimate exhaust gas temperature of an internal combustion engine during ongoing operation of the engine. This comprises determining states of a plurality of parameters of a combustion charge. A heat release of the combustion charge is estimated based thereon, and an exhaust gas temperature is estimated based upon the estimated heat release. Exemplary parameters of the combustion charge comprise engine speed, mass air flowrate, engine fueling and fuel injection timing, and, recirculated exhaust gas fraction.

Abstract: An engine system is disclosed that monitors for boost leak. The system has an engine, a compressor located upstream of the engine, at least one auxiliary flow device located downstream of the engine, and a computing system operable to determine an estimated value corresponding to a flow of fluid through the compressor. The estimated value takes into account a flow of fluid from the compressor toward the at least one auxiliary flow device distinct from a flow from the compressor toward the engine.