Abstract: When a specified air-fuel ratio F/B control condition is established during supply of a secondary air provided, an air-fuel ratio F/B control is executed, and at this time, an initial value of a target air-fuel ratio is set to a before-catalyst air-fuel ratio detected by an A/F (air-fuel ratio) sensor. The target air-fuel ratio subsequent to this is gradually changed from the initial value to a specified air-fuel ratio. By this, the initial value of the target air-fuel ratio can be suitably set at a start time of execution of the air-fuel ratio F/B control during the supply of the secondary air. The target air-fuel ratio subsequent to this is gradually changed to a stoichiometric air-fuel ratio, so that a change in engine rotation speed is suppressed and the drivability can be improved.

Abstract: Described is a method for controlling a temperature downstream of a catalyst in the exhaust tract of an internal combustion engine including a first control loop in which a first control variable is calculated from a first deviation that is calculated from a first actual value and a first setpoint value and influences an intra-engine heat generation. In the process, the first actual value is determined as a measure of a temperature downstream of the catalyst. The method features a second control loop in which at least one second control variable is calculated from a second deviation that is calculated from a second actual value and a second setpoint value; a temperature upstream of the catalyst being determined as the second actual value. Also described is a controller which controls the sequence of such a method.

Abstract: A combustion control apparatus for an internal combustion engine having an exhaust gas purifier in an exhaust passage, includes a controller that controls supply of fuel and air to the engine. The controller is configured to produce preliminary combustion at or near compression top dead center and main combustion after an end of the preliminary combustion under a predetermined condition based on a condition of the exhaust gas purifier. The controller is further configured to determine a target intake air quantity by adding an increase correction to the target intake air quantity based on a torque correction value and determine a target fuel injection quantity by calculating the target fuel injection quantity from an actual air quantity and a target air/fuel ratio. A combustion control method is also provided.

Abstract: A computer control system is described that monitors the functionality of an emission control device that is capable of storing NOx and oxygen during lean conditions, and releasing/reducing the stored oxygen and NOx during rich operating conditions. The computer uses a readable storage medium having stored data representing instructions executable by a computer. The instructions utilize a ratio between a lean operating time and a rich operating time to determine whether the catalyst has degraded.

Abstract: An engine control device is configured to cause an engine to operate at the optimum combustion mode according to the load when warming up of an emissions purification catalyst is required, and to obtain reduced HC discharged from the engine and accelerated warm-up of the catalyst. The engine control device performs stratified combustion with a compression stroke injection in a low-load region according to the engine load, and performs double-injection combustion with an intake stroke injection and a compression stroke injection in an intermediate load region, when warming up of the catalyst is required. In a high-load region, the engine control device performs homogenous combustion with an intake stroke injection.

Abstract: In an exhaust aftertreatment system, which includes a nonthermal plasma discharge device followed by a NOx storage device followed by a precious metal catalyst, a method is disclosed for operating the engine at a lean air-fuel ratio when the NOx storage device is not full and for operating the engine rich when the NOx storage device is substantially full. Electrical energy supplied to the nonthermal plasma discharge device during lean operation is discontinued during rich operation of the engine.

Abstract: A method for operating an electro motor-driven secondary air pump which is provided for injecting secondary air into the exhaust system of an internal combustion engine. The secondary air pump is operated in a clocked manner. The induced voltage at the electro motor of the secondary air pump, measurable during the turn-off time of the clocked operation, is used for diagnosing as well as for controlling the speed of the secondary air pump. The diagnosis is carried out based on the evaluation of a parameter (difference quotient, differential quotient) of the induced voltage. The induced voltage is instantaneously a measure for the secondary air pump's actual speed value, so that a separate detection of the actual speed value is omitted.

Abstract: A process for controlling an exhaust system can comprise flowing exhaust gas from the engine past a first oxygen sensor, through a NOx adsorber, past a second oxygen sensor, through a catalyst and past a third oxygen sensor, wherein the first oxygen sensor, the second oxygen sensor, and the third oxygen sensor, are in operable communication with an electronic control module, and using a switching delay between the first oxygen sensor and the second oxygen sensor to determine a NOx value, wherein the NOx value is selected from the group consisting of a NOx regeneration time, a stored NOx amount, a NOx storage efficiency, and combinations comprising at least one of the foregoing NOx values. A desulfurization process can be initiated when the NOx value is less than or equal to a first selected value. During the desulfurization process, when the third oxygen sensor signals a condition rich of stoichiometry, oxygen can be provided to the catalyst.

Abstract: There are provided NOx trap catalyst to trap and release NOx based on air-fuel ratio, first fuel supply means for supplying gasoline, second fuel supply means for supplying hydrogen, engine operation detecting means for detecting engine operating condition, fuel ratio changing means for changing the ratio of gasoline and hydrogen, NOx release determining means for determining whether it is required for the NOx to be released based on a state of the trapped NOx, NOx releasing means for releasing the NOx trapped by making the air-fuel ratio rich when the NOx releasing requirement is determined, gasoline ratio increasing means for increasing the ratio of gasoline when NOx releasing requirement is determined and the air-fuel-ratio rich control is executed. Accordingly, improper vibrations or noises can be restrained from occurring when the rich air-fuel-ratio control is executed to release the trapped NOx from the NOx trap catalyst.

Abstract: A failure diagnosis apparatus for secondary air supplier according to the present invention determines a failure of a secondary air supplier based on pressure and pressure pulsation in a secondary air supply path. A failure diagnosis is made by determining the presence or absence of pressure pulsation in the secondary air supply path based on a determination threshold, and in the present invention the determination threshold is varied according to a pressure value in the secondary air supply path (a smoothed value or an average value of measured pressure). This permits the apparatus to make an accurate failure diagnosis, while eliminating pressure pulsations except for that due to exhaust pulsation (e.g., that due to noise of the pressure sensor and that caused by surging of an air pump).

Abstract: A canister communicates with an intake manifold of an internal combustion engine through a purge pipe. The canister absorbs fuel vapor evaporated in a fuel tank. The absorbed fuel vapor is purged into the intake manifold when the engine is on. A gas leak check module communicates with the canister for drawing air by an air suction pump 43. When the engine is off, the air suction pump is driven and draws hydrocarbon floating at a vicinity of an intake port through the purge pipe. Thus, the hydrocarbon floating at the vicinity of the intake port is absorbed in the canister so that emission of hydrocarbon is reduced.

Abstract: An exhaust gas purifying system for an internal combustion engine is arranged to determine a recovery execution timing for recovery processing of recovering an exhaust gas purifying device such as a particulate filter and a NOx trap catalyst from a specific content stacked state, to determine a target air/fuel ratio for executing the recovery processing, to determine a first engine controlled variable relating to an air/fuel ratio on the basis of the target air/fuel ratio, and to determine a second engine controlled variable relating to a combustion period at a value different from a value employed during normal processing when the recovery processing is executed.

Abstract: A controller executes temperature rise control on a catalyst device by retarding ignition timing that is set based on engine operating conditions. The controller reaches a diagnosis that the temperature rise control is normal if an advance angle side accumulated time for which the ignition timing is set exceeding a threshold value to an advance angle side during execution of the temperature rise control is less than an accumulated time determination value. When the advance angle side accumulated time is greater than or equal to the accumulated time determination value, the controller reaches a diagnosis that the temperature rise control has an anomaly.

Abstract: An operating method for an internal combustion engine is described, especially for a motor vehicle, in which, in a first operating mode, fuel is injected preferably for heating a catalytic converter and, in at least one further operating mode, into a combustion chamber. In order to prevent a sudden change in the torque produced by the internal combustion engine during the switchover from/to the first operating mode, a distribution factor influencing torque is taken into account in an actual branch and/or in a setpoint branch of controller of the internal combustion engine.

Abstract: In a secondary air injection system, MOSFETs control supply of electric current to an air pump and to a motor for driving an electromagnetic valve and to an electromagnetic coil to introduce secondary air into an exhaust gas passage upstream of a catalyst for purifying the exhaust gas of an internal combustion engine. Gate drive circuits control the MOSFETs based on an instruction from an ECU via input signal processing circuits. Abnormal conditions in the operation for controlling the air pump and the electromagnetic valve are detected, and, when an abnormal condition is detected, forcibly turn the MOSFETs off to interrupt the current to the motor and to the electromagnetic coil. A diagnosing circuit sends to the ECU diagnosis signals representing the state of controlling the load.

Abstract: In an exhaust system of an internal combustion engine, an air-fuel ratio sensor is located upstream of a three-way catalyst. An oxygen sensor is located downstream of the catalyst. An ECU performs feedback control of the amount of fuel based on output of the air-fuel ratio sensor such that the engine air-fuel ratio seeks a stoichiometric air-fuel ratio. The ECU also performs sub-feedback control for correcting the amount of fuel in the feed back control based on output of the oxygen sensor. The ECU learns a learning value for compensating for a stationary difference between the engine air-fuel ratio and the stoichiometric air-fuel ratio based on a sub-feedback correction value. When learning of the learning value is performed after the learning value is cleared, a slip control by a lockup clutch is inhibited until the learning is stabilized.

Abstract: A an improvement in a two wheel motor vehicle having an internal combustion motor and a wheel drive mechanism, wherein the motor has an exhaust system connected thereto, includes a) an exhaust system having a first exhaust pipe and a second exhaust pipe with the first exhaust pipe being in a fixed position relative to the internal combustion motor, and the second exhaust being rotatably connected to the first exhaust pipe, and b) an exhaust pipe drive mechanism connected to the second exhaust pipe for rotation of the second exhaust pipe. The pipe drive mechanism may operate off some power source of the vehicle, operate independently of the vehicle power sources, may operate from exiting exhaust gases, ambient wind form motion of the vehicle, or a combination of the foregoing.

Abstract: A motor vehicle having at least three wheels, an internal combustion motor and a wheel drive mechanism, wherein the motor has an exhaust system connected thereto, includes a) an exhaust system having a first exhaust pipe and a second exhaust pipe with the first exhaust pipe being in a fixed position relative to the internal combustion motor, and the second exhaust being rotatably connected to the first exhaust pipe, and b) an exhaust pipe drive mechanism connected to the second exhaust pipe for rotation of the second exhaust pipe. The pipe drive mechanism may operate off some power source of the vehicle, operate independently of the vehicle power sources, may operate from exiting exhaust gases, ambient wind form motion of the vehicle, or a combination of the foregoing.

Abstract: An exhaust emission control system for an internal combustion engine includes a filter that traps particulate matters and ash and a controller that starts a filter recovery process by controlling a temperature of the filter to a target temperature to bring an inside of the filter into an oxidizing atmosphere such that the particulate matter trapped and accumulated on the filter is removed through oxidization when an estimated amount of the particulate matters trapped and accumulated on the filter exceeds a predetermined amount. The target temperature is set based on the estimated amount of the ash trapped and accumulated on the filter. Even if the amount of the accumulated particulate matter per unit volume is increased owing to accumulation of the ash on the filter, and oxidization reaction speed of the particulate matter may be reduced, thus preventing excessive temperature increase in the filter.

Abstract: A regeneration control device, which regenerates a filter (13) for trapping particulate matter in exhaust gas from an engine (1), is disclosed. The filter (13) supports a catalyst which oxidizes unburnt components in the exhaust gas. The regeneration control device has a temperature sensor (14) which detects a filter inlet exhaust gas temperature (Tdpf_in_mea); and a microcomputer (22). The microcomputer (22) is programmed to compute a filter outlet exhaust gas temperature (Tdpf_out_cal), not including temperature rise due to oxidation reaction of unburnt components based on the detected inlet exhaust gas temperature; compute the filter bed temperature (Tbed_cal) based on the detected inlet exhaust gas temperature and computed outlet exhaust gas temperature; compute a temperature rise (?Thc1) due to oxidation reaction of unburnt components; correct the bed temperature based on the computed temperature rise (?Thc1).