Abstract: There is disclosed a leakage diagnosis of an evaporative system in an internal combustion engine, and more particularly there is disclosed an evaporative system in which a more accurate leakage diagnosis can be effected using a change in the pressure in the evaporative system, and such a diagnosis method is also disclosed. The evaporative system includes a gauge line having a gauge valve, which gauge line branches off from an evaporative gas line or an evaporative gas purge line, and communicates with a point upstream of an engine throttle valve or with the ambient atmosphere, a pressure sensor for detecting the pressure in the evaporative system, and a purge valve. A leakage diagnosis of this system is effected based on detected values of the pressure sensor obtained by opening and closing the purge valve and the gauge valve. Therefore, accurate results of the diagnosis can be obtained.

Abstract: A diagnosis apparatus for diagnosing a catalystic converter of a motor vehicle as to whether the catalyst suffers deterioration by estimating a temperature of the catalyst or that of the exhaust gas in the vicinity of the catalyst on the basis of a plurality of engine parameters to thereby decide deterioration of the catalyst by using as an index the estimated temperature. The apparatus includes a unit for estimating the temperature of the catalyst in a steady state by making use of an engine speed and an engine load which represent typical parameters employed in fuel injection control of the engine. The steady-state temperature facility is realized by storing the engine speeds and the engine loads obtained experimentally in the steady state operation of the engine in the form of a two-dimensional data map.

Abstract: The object of this invention is that a suction devise for an internal combustion engine is to be compact.The suction devise comprising a casing having an air inlet and a plurality of outlets, a filter in the casing for filtering air from said air inlet, a collection chamber in the casing for receiving air from the filter, at least one throttle valve in the casing for controlling the flow of air from said filter to said collection chamber, and a plurality of suction pipes.According to the present invention, the suction device can be made compact to thereby effectively use an engine room of an automobile.

Abstract: It is an object to improve the opening control resolving power in the case where the opening/closing of a throttle valve is controlled by a motor driven actuator. An additional control signal for finely vibrating the throttle valve is given to the actuator in a specific period until the opening of the throttle valve approaches its target value. Consequently, the throttle valve vibrates finely only as occasion demands. Accordingly, in spite of the fact that the opening of the throttle valve can be controlled with finer control resolving power than ordinary control resolving power, good response can be obtained as a whole.

Abstract: A diagnosis apparatus for diagnosing a catalytic converter of a motor vehicle as to whether the catalyst suffers deterioration by estimating a temperature of the catalyst or that of the exhaust gas in the vicinity of the catalyst on the basis of a plurality of engine parameters to thereby decide deterioration of the catalyst by using as an index the estimated temperature. The apparatus includes a unit for estimating the temperature of the catalyst in a steady state by making use of an engine speed and an engine load which represent typical parameters employed in fuel injection control of the engine. The steady-state temperature facility is realized by storing the engine speeds and the engine loads obtained experimentally in the steady state operation of the engine in the form of a two-dimensional data map.

Abstract: A control apparatus for a multicylinder direct injection engine includes a fuel injection valve installed at each cylinder, a secondary intake air flow path provided for generating a slewing flow of intake air taken in an intake pipe, and a gas flow control valve for controlling the slewing flow generated in each cylinder by adjusting the flow rate of air flowing through the secondary intake air flow path. The control apparatus further includes an air/fuel controller for controlling the air/fuel control ratio in each cylinder by controlling fuel injection amount without using the opening of the gas flow control valve in the respective cylinder, for a first operational region of a small amount of accelerator operation.

Abstract: In order to prevent a catalyst for an internal combustion engine from experiencing decreased efficiency by deterioration after long time use of the catalyst, the decreased efficiency of the catalyst is determined, and the internal engine is controlled based on results of the determination so as to maintain high efficiency of the catalyst. The catalyst is installed in an exhaust pipe of the engine. Sensors for detecting conditions of exhaust gas both at a upstream side and a downstream side of the catalyst are provided, respectively. As for the sensor, for example, an oxygen sensor whose output varies stepwise at .lambda.=1, or a sensor whose output varies in proportion to air-fuel ratio can be used. Detected values of the sensors are taken into a control unit, catalyst efficiency and deteriorating degree of the catalyst are estimated by comparison of the detected values, and the engine is controlled so that the catalyst efficiency is maximized.

Abstract: An engine control unit is configured to detect the revolution of an engine and to obtain the intensity of both the first order component of revolution for every combustion (one cycle per combustion) and the second order component of revolution. The second order is twice as much as the first order component. The unit further obtains dispersion or deviation in these intensities. Thereby, it is possible to detect combustion conditions and to correct them to desirable conditions.

Abstract: The suction is provided as an integral member which includes a casing having an air inlet and a plurality of ports forming outlets to the engine cylinders, a filter in the casing for filtering air flowing through the air inlet, a collection chamber in the casing for receiving air from the filter, at least one throttle valve in the casing for controlling the flow of air from said filter to said collection chamber, and a plurality of suction pipes for communicating with the respective cylinders of the engine through said outlets. The suction device can be made compact to thereby more effectively use the engine compartment of an automobile.

Abstract: An engine control method and apparatus wherein a combustion state in each cylinder of an internal combustion engine is detected based on the fluctuation the rotating angular speed of an engine. A correction control is performed to make the combustion states in each of the cylinders uniform, followed by the base value for the purpose of correction control is obtained when the fluctuation in the rotating angular speed is small.

Abstract: In an evaporated fuel gas purging system, an accurate diagnosis can be realized by providing a reference leakage apparatus (a gauge) having a preset amount of leakage, by intentionally causing a known leakage using the gauge means under the same condition of diagnosing a leakage, and by comparing the pressure change with the pressure change in using the reference leakage apparatus. In the process of diagnosing leakage by depressurizing or pressurizing and closing the inside of the evaporated fuel gas purging system so as to leave it under presence of pressure differences to the atmospheric pressure and then by detecting the pressure change, a difference occurs in the pressure changes inside the evaporated fuel gas purging system between when the gauge is opened and closed. Then sensitivity of the difference in the pressure changes to the leakage is improved under the condition during diagnosis such as fuel temperature, atmospheric pressure, amount of remaining fuel, fuel properties and so on.

Abstract: An automatic transmission control system for an automobile, comprising a vehicle weight estimation unit which estimates a vehicle weight of the automobile a torque estimation unit which estimates an output torque, an acceleration input unit which accepts an acceleration signal; a load estimation unit (110) which estimates a running load from the estimated vehicle weight, the estimated output torque and the accepted acceleration; a memory which stores a plurality of shift schedules therein; and a gear position determination unit (109) which includes the memory, and which selects one of the shift schedules in accordance with the vehicle weight and the estimated running load, so as to determine a gear position of an automatic transmission of the automobile in conformity with the selected shift schedule. An exact shift operation conformed to the vehicle weight and the running load can be performed, and an enhanced fuel consumption can be attained.

Abstract: A control device for an internal combustion engine capable of conducting lean burn control, such as exhaust gas emission control, always optimally regardless of a timewise change of the internal combustion engine, variations in engines, and an environmental change. The control device includes a detector for detecting a burn condition of the internal combustion engine, a lean limit air-fuel ratio factor map, a lean burn feedback logic, an oxygen concentration sensor, and a feedback control logic for controlling an air-fuel ratio to a theoretical air-fuel ratio, wherein lean burn is performed at the middle point between the lean limit air-fuel ratio and the theoretical air-fuel ratio.

Abstract: A total control system for an automotive vehicle assures vehicular behavior precisely following to a driver's demand for variation of driving environment and provide smooth transition in variation of the driving environment. The system includes a driving environment index predicting section predicting vehicular driving environment on the basis of a driving operation indicative amount, such as an accelerator depression magnitude, a brake depression magnitude, a steering angular position and so forth and a vehicular condition indicative amount, such as an engine speed, a vehicle speed, a longitudinal acceleration and so forth. Based on the driving environment index derived by the predicting section, local control channels of the automotive vehicle are controlled. The driving environment index predicting section predicts the driving environment index by neural network or so forth to transfer to the local control channels though a vehicular local area network or a common memory.

Abstract: A torque detection mechanism can be provided for a power train and its control unit without newly adding a sensor and its signal processing module. As a gear pair for the torque detection mechanism of a phase difference type, existing gears in a transmission are used, or a gear pair for this mechanism are provided adjacent to these existing gears. From phase signals sent from pickups, a phase difference signal is obtained by use of one part of existing devices in the control unit. The torque detection mechanism can be realized with the minimum number of component parts by utilizing the existing members and spaces instead of newly adding a sensor and its module. The invention can be applied to either of FF and FR cars, and has a practical structure in respect of the performance, costs and reliability.

Abstract: A NOx reducing catalyst can most efficiently remove both NOx and HC when concentrations of NOx and HC in exhaust have a specified relationship between them. For this purpose, an apparatus is adapted to control the concentrations of NOx and HC at an upstream of a catalyst to have a specified relationship. Sensors for detecting the concentration of NOx and HC are arranged at an upstream side of the catalyst. Additionally, a device for levelling a quantity of HC discharge is disposed to suppress variation thereof.

Abstract: Knocking detecting in an internal combustion engine uses, a vibration sensor detecting engine vibrations; and insert for taking-in output vibration signals from the vibration sensor in a plurality of intervals in a time sequential manner during every explosion stroke of the internal combustion engine; performing a digital frequency analysis on the taken-in output vibration signals in the respective sequential intervals; setting a main resonance frequency necessary for knocking occurrence judgement based upon the instant operating condition of the internal combustion engine; calculating knocking indexes for the digital frequency-analyzed output vibration signals in the respective sequential intervals based upon the set main resonance frequency component; comparing the largest knocking index calculated with a predetermined threshold value determined by a background vibration level and a slice level thereof to determine occurrence of knocking; and renewing the respective background vibration levels using the cal

Abstract: A system which is capable of diagnosing the deterioration condition of an engine exhaust gas purifying device has front and rear air/fuel ratio sensors for detecting the air/fuel ratio of the exhaust gas upstream and downstream of the catalyst, an autocorrelation function calculation for calculating the autocorrelation function .phi.xx of an output signal from the front air/fuel ratio sensor to output the maximum values (.phi.xx)max of the autocorrelation function .phi.xx at predetermined intervals, each maximum value (.phi.xx)max being in each of the predetermined intervals. A cross-correlation function calculator calculates the cross-correlation function .phi.xy between the output signals from the front and rear air/fuel ratio sensors to output the maximum values (.phi.xy)max of the mutual correlation function .phi.xy at predetermined intervals, each maximum value (.phi.xy)max being in each of the predetermined intervals therefore. The ratios between the maximum values (.phi.xy)max and (.phi.

Abstract: An air intake arrangement for an internal combustion engine comprising: a main air intake conduit leading to a gas intake valve (241 ) for respective engine cylinders (206 ) and including a main air intake passage (202 ), a main collector chamber (204 ) and independent branching air intake passages (205) for the respective engine cylinders (206) connected in series; a throttle valve (203 ) disposed in the main intake air passage (202 ) for controlling the flow rate of air passing therethrough; an auxiliary air intake passage (210 ) bypassing the main air intake conduit, an inlet port of the auxiliary air intake passage (210 ) opens into the main air intake passage (202) at the upstream of the throttle valve (203 ), an outlet port (213 ) of the auxiliary air intake passage (210 ) opens into the respective independent branching air intake passages (205) near the gas intake valve (241) for the respective engine cylinders (206 ) in such a manner that gas blown-out from the auxiliary air intake passage (210 ) indu

Abstract: A system and method for controlling ignition timing for an internal combustion engine to suppress engine knocking in which a periodic pseudo random signal (for example, M-series sequence signal) is superimposed on an ignition signal provided at an ignition timing, and a cross-correlation function between the periodic pseudo random signal .chi. and a knocking signal y is calculated to determine an actual knocking level. The ignition timing is then corrected so that the cross-correlation function coincides with a target value which is defined as a value placed in a vicinity of a knocking limit. The ignition timing for the engine is controlled so as to reach the value in the vicinity of the knocking limit but does not exceed the knocking limit.