Abstract: A system for controlling an idle speed of an internal combustion engine having an electrically heated catalytic converter which is heated up when current is supplied from an alternator driven by the engine. In the engine idle control, a basic value of a desired idle engine speed is determined with respect to the engine coolant temperature in the same manner as the prior art. However, an augmentative correction amount of the desired idle engine speed is determined with respect to the exhaust system ambient temperature. More specifically, the desired idle engine speed is increased in response to the heating of the catalytic converter so as to prevent the alternator from generating electric power insufficient for heating up the catalytic converter.

Abstract: A system and method for detecting a failure occurring in an exhaust secondary air supply system of an internal combustion engine. A conduit is connected to the exhaust pipe to supply secondary air to the exhaust pipe to promote oxidization of the emissions in the exhaust gases. A valve is provided in the conduit for opening/closing it. The failure of the valve is detected by operating the air pump to supply the air in the conduit, while closing the conduit by the valve. The air/fuel ratio is detected by an oxygen sensor installed downstream of the conduit to be compared with a desired air/fuel ratio. If the detected air/fuel ratio is leaner than a desired air/fuel ratio, the air flows to the exhaust pipe so that the valve is considered to be stuck to open. Alternatively, a pump current is detected and is compared with a reference value indicative of the current at no air flow. If the detected current is less than the reference value, the valve is considered to be in failure.

Abstract: A motor vehicle alternator connected to an output shaft of an internal combustion engine mounted on a vehicle, comprising a rotor made of a permanent magnet for producing a magnetic field, an armature (stator) having a coil placed opposite to the permanent magnet rotor and a belt drive mechanism for connecting one of the permanent magnet and the armature to the output shaft of the engine to bring them into a relative rotation such that the armature relatively moves in the magnetic field produced by the permanent magnet. In the alternator, there is provided an axial displacement mechanism for displacing at least one of the permanent magnet rotor and the armature in an axial direction of the relative rotation, whereby a magnetic flux passing through the armature is changed.

Abstract: A system for detecting a failure of an electrically heated catalytic converter installed in an exhaust system of the engine for reducing pollutants from exhaust gases emitted from the engine, the catalytic converter having a heater which is connected with the power source to be supplied with current. A parameter such as electric power consumption indicative of an electric resistance of the heater of the catalytic converter. If the parameter is out of a range defined by reference values, it is determined hat a failure has occurred in the heater of the catalytic converter. In the system, reference values at a specific condition based on a correction coefficient obtained on the ratio between the parameter designed before manufacturing and that measured after manufacturing.

Abstract: A control system for controlling an alternator driven by an engine, for generating electric power, has a changeover switch for selectively switching destination of electric power generated by the alternator to a plurality of electric loads having respective different load voltage values. An ECU controls switching operation of the changeover switch and controls the alternator electric power, according to a direction in which the changeover switch has been switched.

Abstract: A combustion state-detecting system for internal combustion engines has a crank angle sensor which generates a crank angle signal with a predetermined period shorter than the firing period of the engine whenever the crankshaft rotates through a predetermined angle. A value of the rotational speed of the engine is detected whenever the crank angle signal is generated. An average value of the detected engine rotational speed is calculated over every period of one rotation of the crankshaft. A difference amount between a newest value of the average value of the detected engine rotational speed and a value of the average value calculated a predetermined number of firing periods earlier is calculated. The combustion state of the engine is detected based on the difference amount.

Abstract: A system for detecting the ambient temperature of an exhaust system of an internal combustion engine, where an oxygen sensor (O.sub.2 sensor) is installed for detecting oxygen content in exhaust gases generated by the engine. The oxygen sensor has a detection element and a heater for heating the detection element when supplied with current. The exhaust system is further provided with a catalytic converter which similarly has a heater for heating the catalyst for promoting the activation thereof. The electric resistance of the sensor heater is detected and based on the detected resistance, the ambient temperature of the exhaust system is detected or estimated in accordance with characteristics preestablished with respect to the electric resistance of the heater. With the arrangement, it becomes possible to detect the ambient temperature of the exhaust system without using a temperature sensor. The detected ambient temperature is used for controlling the current supply to the heater of the catalytic converter.

Abstract: An air pump abnormality-detecting system for an internal combustion engine. The engine has a catalyst arranged in the exhaust system of the engine, a passage extending from the exhaust system at a location upstream of the catalyst, and an electrically driven air pump arranged across the passage, for supplying secondary air into the exhaust system. A current sensor detects electric current flowing through the air pump, and a voltage sensor detects voltage applied to the air pump. An abnormality of the air pump is detected by comparing an output from the current sensor obtained during operation of the air pump, with predetermined abnormality-detecting reference values. At least one of the output from the current sensor or the predetermined abnormality-detecting reference values is corrected in response to an output from the voltage sensor.

Abstract: A current control system of an electrically heated catalytic converter installed in the exhaust system of an internal combustion engine. In the engine, fuel metering is controlled by correcting a basic quantity of fuel injection by correction factors. The correction factors are grouped into the factors for increasing the fuel injection quantity at engine warmup and other factors. Therefore, the total value of the factors for increasing the fuel injection quantity at engine warmup are compared with a predetermined value, and if the total value exceeds the predetermined value, the current supply to the heater is inhibited. Alternatively, the cranking time is compared with a predetermined value and if it exceeds the predetermined value, the current supply is inhibited. Since the quantity of fuel injection is increased in these situations, unburned emissions will accordingly be increase.

Abstract: An exhaust gas-purifying device for an internal combustion engine has an adsorbing device arranged in an exhaust passage of the engine for adsorbing unburnt fuel components in exhaust gases from the engine, a catalytic converter arranged in same at a location downstream of the adsorbing device for purifying the exhaust gases, and a heater for electrically heating the catalytic converter. The temperature of the adsorbing device is detected. The heater is controlled to be operated at least on condition that the temperature of the adsorbing device is above a predetermined value. In another form of the invention, the temperature of the catalytic converter is detected. A rate of a rise of the temperature of the catalytic converter is determined. A deterioration state of the adsorbing device is determined based on the rate of the rise of the temperature of the catalytic converter.

Abstract: An exhaust gas-purifying system for an internal combustion engine includes an alternator driven by the engine. A regulator controls voltage generated by the alternator. An electrically-heated catalyzer is arranged in the exhaust system of the engine and connected to the alternator to be electrically heated by electric power generated by the alternator. An ECU controls the regulator to control the voltage generated by the alternator and supplied to the electrically-heated catalyzer, according to a degree of aging of the electrically-heated catalyzer.

Abstract: A combustion state-detecting system for an internal combustion engine comprises a rotational speed sensor for detecting a value of the rotational speed of the engine with a predetermined repetition period shorter than the firing period of the spark plug whenever the crankshaft rotates through a predetermined angle, and an ECU which calculates a difference amount between a value of the detected rotational speed of the engine and a value of the detected rotational speed of the engine a predetermined number of firing periods earlier. A combustion state of the engine is detected based on the calculated difference amount.

Abstract: An exhaust gas-purifying device for an internal combustion engine has an adsorbing device arranged in an exhaust passage of the engine for adsorbing unburnt fuel components in exhaust gases from the engine, a catalytic converter arranged in same at a location downstream of the adsorbing device for purifying the exhaust gases, and a heater for electrically heating the catalytic converter. The temperature of the adsorbing device is detected. The heater is controlled to be operated at least on condition that the temperature of the adsorbing device is above a predetermined value. In another form of the invention, the temperature of the catalytic converter is detected. A rate of a rise of the temperature of the catalytic converter is determined. A deterioration state of the adsorbing device is determined based on the rate of the rise of the temperature of the catalytic converter.

Abstract: A secondary air pump control system for an internal combustion engine having an air pump for supplying secondary air to the exhaust passage, comprises a voltage detector for detecting voltage applied to the air pump, a current detector for detecting current flowing through the air pump, and a switch for making a changeover between supply of electric power to the air pump and cutoff of same. The flow rate of secondary air supplied by the air pump is detected based on an output from the voltage detector and an output from the current detector. The operation of the switch is controlled based on the flow rate thus detected.

Abstract: An exhaust gas-purifying system for an internal combustion engine includes a catalyzer arranged in the exhaust system of the engine. The catalyzer is provided with a heater for heating the same. An ECU controls the operation of the heater. The ECU is responsive to operating conditions of the engine detected by engine operating parameter sensors, for restraining the operation of the heater.

Abstract: A high probability of detecting an erroneous misfire occurs when combustion becomes unstable during jolt control. Therefore, during jolt control the reliability of the misfire detection system is degraded. As a result, the misfire detection system is inactivated during jolt control by discontinuing the misfire detection, or by deliberately deeming no misfire has occurred if jolt control has occurred. Alternatively, the misfire detection sensitivity is masked during jolt control.

Abstract: An adsorber temperature-estimating device for an internal combustion engine comprises an adsorber arranged in the exhaust passage, for adsorbing an unburnt gas component present in exhaust gases emitted from the engine. Operating parameter sensors detect operating parameters of the engine, and an ECU estimates the temperature of the adsorber, based on the detected operating parameters. An exhaust gas-purifying system for the engine comprises the adsorber, a catalytic converter arranged in the exhaust passage at a location downstream of the adsorbing means, for purifying exhaust gases, and a secondary air supply pump for supplying secondary air to the exhaust passage at a location upstream of the catalytic converter. The ECU controls an amount of secondary air to be supplied to the exhaust passage, based on the estimated temperature calculated by the adsorber temperature-estimating device.

Abstract: A control system controls an electrically heated catalyst for purifying exhaust gases emitted from an internal combustion engine. Voltage applied to the electrically heated catalyst and electric current flowing through the same are detected. A changeover is made between supply and interrupt of power to the electrically heated catalyst. A parameter indicative of an operative state of the electrically heated catalyst is calculated based on the detected voltage and the detected current, and the operative state of the electrically heated catalyst is detected based on the parameter. The changeover between the supply and interrupt of power to the electrically heated catalyst is controlled based the operative state of the electrically heated catalyst thus detected.

Abstract: An adsorbing capacity determining apparatus is provided for determining the adsorbing capacity of an unburned component adsorbing device in an exhaust system for an internal combustion engine. The adsorbing capacity determining apparatus comprises upstream and downstream air-fuel ratio detectors, respectively coupled upstream and downstream from the unburned component adsorbing device, a temperature sensor for sensing the temperature of the unburned component adsorbing means and a computer for determining the adsorption capacity as a function of the outputs of the system and downstream air-fuel ratio detectors, when the temperature is within a predetermined range.

Abstract: An exhaust gas-purifying system for an internal combustion engine has an adsorbing device arranged in an exhaust passage thereof for adsorbing or desorbing unburnt component contained in exhaust gases. An exhaust gas recirculation passage branches off from the exhaust passage at a branch point downstream of the adsorbing device and extending to an intake passage of the engine for returning exhaust gases flowing through the adsorbing device to the intake passage. The path of exhaust gases is changed to selectively introduce the exhaust gases containing the unburnt components into the exhaust gas recirculation passage. The adsorbing capacity of the adsorbing device is checked based on a manner of change in an air-fuel ratio of exhaust gases detected when the exhaust gases are introduced into the exhaust gas recirculation passage.