Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Other

Tokiji Ito

Hideki Miyahara

Kenji Nagasaki

Masashi Hakariya

Yoshihisa Oda

Isao Nakajima

Yuya Yoshikawa

Yoshifumi Matsuda

Shuichi Hanai

Hiroaki Tsuji

Toshihiro Kato

Masahide Okada

Noriyuki Iden

Akihiro Katayama

Masatomo Yoshihara

Yuichi Kohara

Fumito Takimoto

Naohide Fuwa

Yasuo Kato

Masao Kano

Yoshiyuki Shogenji

Kota Hayashi

Akira Ichikawa

Shin Adachi

Tatsuro Shimada

Susumu Shinohara

Seiko Tamada

Takashi Yui

Hiroyuki Kanemoto

A control device includes an engine valve and a variable valve actuation mechanism that is able to change at least one of a valve operating angle and valve lift of the engine valve. When the at least one of the valve operating angle and the valve lift is larger than or equal to a prescribed upper limit, the control device increases an operating speed of the variable valve actuation mechanism as compared with when the at least one of the valve operating angle and the valve lift is smaller than the prescribed upper limit.

Control device and control method for variable valve actuation mechanism

A control device of an internal combustion engine according to the present invention executes air-fuel ratio control based on an output of an air-fuel ratio sensor provided at an upstream side of a catalyst, with correction based on an output of an oxygen sensor at a downstream side of the catalyst. When it is determined that a degree of an output tendency in a predetermined lean region is not less than a predetermined lean degree, and that a degree of an output tendency in a predetermined rich region is less than a predetermined rich degree based on lean tendency and rich tendency values representing output tendencies of the oxygen sensor, a limit is set to the correction in a direction to more suppress enriching of an air-fuel ratio as a degree is larger in which the output of the oxygen sensor is shifted to a lean side.

Control device of internal combustion engine

An air-fuel ratio control apparatus for an internal combustion engine is provided. A controller is programmed to perform correction amount guard control allowing adjustment of a correction amount by setting a limit on the correction amount when an appearance frequency of a state where an output value from a downstream sensor is leaner than a predetermined value is equal to or higher than a predetermined value. When a state where the output value from the downstream sensor is leaner than the predetermined value lasts for a duration equal to or longer than a predetermined time, an incorporation speed at which, during learning control, the correction amount for sub feedback control is incorporated into a learning value is set to a larger value that when the duration is shorter than the predetermined time, and performance of the correction amount guard control is suppressed until the learning control is completed.

Air-fuel ratio control apparatus for internal combustion engine

An abnormality detecting device of an internal combustion engine according to the present invention includes a sensor nick abnormality detecting unit configured to detect a nick abnormality in a detecting element of a downstream side sensor which is provided in a downstream side of an exhaust gas purifying catalyst in an exhaust passage and generates an output corresponding to an oxygen concentration in exhaust gas, on the basis of a matter that a distribution of an output of the downstream side sensor is biased to an area in which the air-fuel ratio is leaner than a theoretical air-fuel ratio, and an inhibiting unit configured to inhibit detection of the nick abnormality of the detecting element by the sensor nick abnormality detecting unit in the case that an intake air amount exceeds a predetermined amount.

Abnormality detecting device of internal combustion engine

A control device of an internal combustion engine according to the present invention has units configured to inject fuel at a first predetermined ratio from first and second fuel injection valves which are provided in each of cylinders to calculate a first value indicating a degree of variation in air-fuel ratios between the cylinders based on a output of the engine, and inject fuel at a second predetermined ratio therefrom to calculate a second value in the same manner. Furthermore, the control device has a unit configured to select one mode from modes relating to abnormality in the first fuel injection valve or the second fuel injection valve on the basis of the first and second values, and calculate a value indicating the degree of the variation in the air-fuel ratios between the cylinders, thereby calculating a fuel amount of the basis of them.

A detecting apparatus that detects an abnormality of imbalance of air-fuel ratios among cylinders of a multi-cylinder internal combustion engine, which is equipped with a variable working angle mechanism of an intake valve, the detecting apparatus includes an abnormality detection portion that detects a parameter regarding rotational fluctuations of each of the cylinders and detects whether or not there is an abnormality of imbalance of air-fuel ratios among the cylinders. The abnormality detection portion refrains from determining that the air-fuel ratios are normal when the working angle at the time of detection of the parameter is within a predetermined large working angle range, and determines that the air-fuel ratios are normal when the working angle at the time of detection of the parameter is within a predetermined small working angle range that is on a small working angle side with respect to the large working angle range.

Apparatus and method for detecting abnormality of imbalance of air-fuel ratios among cylinders

A control apparatus of a variable valve system includes a variable valve timing mechanism that performs variable control of the valve timing of an intake valve of an internal combustion engine, a variable operation angle mechanism that performs variable control of the operation angle of the intake valve, and a control unit that performs drive control of the variable valve timing mechanism and the variable operation angle mechanism. The control unit sets an upper guard for the operation angle according to an actual value of the valve timing, and when a target value of the valve timing is a value on the retard side of a specified determining value, the control unit reinforces the upper guard compared with when the target value of the valve timing is not a value on the retard side of the specified determining value.

Variable valve system control apparatus

An internal combustion engine includes a valve timing change mechanism that changes the phase of an intake cam, and a lift amount change mechanism that changes lift amount by causing displacement of a control shaft. An electronic control unit performs a coordinated control in which the lift amount change mechanism is operated such that the position of the control shaft that is detected by a position detection sensor becomes the target position, and the valve timing change mechanism is operated according to a control state of the lift amount change mechanism. When a discrepancy between the actual position of the control shaft and the detected position thereof is estimated to be large, coordinated control is forbidden and the valve timing change mechanism is operated based on engine load.

Control apparatus and control method for internal combustion engine

An actuator control apparatus includes: an actuator that changes a state amount of an internal combustion engine; a sensor that detects an actual operation position of the actuator; a controller that controls the actuator to bring the actual operation position of the actuator to a target operation position set based on the operation state of the internal combustion engine; and a diagnosis portion that diagnoses the operation state of the actuator to be normal if the deviation between the target operation position and the actual operation position has been small for a predetermined time period and the amount by which the target operation position has changed in the predetermined time period is equal to or larger than a predetermined value. A method for controlling such an actuator control apparatus is also provided.

Actuator control apparatus and method

A cooling apparatus includes a thermostat that adjusts a feed rate of coolant to a radiator, estimating means that estimates a coolant temperature simulated value at least based on the detection value of an intake-air temperature sensor, and diagnosis means that diagnoses an operating state of the thermostat by comparing the detection value of a coolant temperature sensor, and the coolant temperature simulated value when a diagnosis condition is established. When a ratio of an integrated value of the simulated water temperature variation in an idle state to the integrated value of the simulated water temperature variation in a normal driving state is equal to or greater than an upper limit ratio XP, the diagnosis of the operating state of the thermostat is prohibited.

Cooling apparatus for internal combustion engine

A cooling apparatus for an engine is provided with a thermostat operating in such a manner as to control a supply of a coolant to a radiator. An electronic control apparatus estimates a reference temperature corresponding to a temperature of the coolant on the basis of at least a vehicle speed, and diagnoses an operating state of the thermostat on the basis of a comparison between a detected value of the coolant temperature and the reference temperature. The electronic control apparatus inhibits the diagnosis of the operating state of the thermostat in the case that any one of the following conditions i) to iii) is satisfied.

Cooling apparatus for internal combustion engine and diagnosis method for the cooling apparatus

A suction pump introduces negative pressure into a reference-pressure-detecting portion. A driving voltage V of the suction pump is adjusted in such a manner that pressure Pr in the reference-pressure-detecting portion is within a target pressure range. When the pressure Pr is brought into the target pressure range, the driving voltage V of the suction pump is stored as a first driving voltage Vand the pressure Pr is stored as a reference pressure Pr. When pressure detection and leak detection process are conducted, the suction pump is driven at the first driving voltage Vto introduce the negative pressure. The computer compares the pressure Pr with a leak determination value to determine whether a leak exists.

Leak detector for fuel vapor purge system

After a reference pressure using a reference hole is measured, a pressure in an evaporation path is measured. An ECU conducts failure diagnosis using, as a determination pressure for diagnosing presence/absence of a failure, a value obtained by correcting the reference pressure using the reference hole in a manner lowering the same by a predetermined amount, taking into account pressure lowering in the evaporation path due to condensation of fuel vapor at the time of adsorption in a canister when a vapor concentration in the evaporation path is high.

Failure diagnostic apparatus for fuel vapor purge system and fuel vapor purge apparatus and combustion engine having failure diagnostic apparatus

When a purge amount while an engine is running is a first purge amount and the purge amount before failure diagnosis is larger than a required purge amount, an amount adsorbed in a canister before the failure diagnosis is executed is smaller than a predetermined determination value. Accordingly, an ECU executes the failure diagnosis. When the purge amount while the engine is running is a second purge amount and the purge amount before the failure diagnosis is equal to or smaller than the required purge amount, the amount adsorbed in the canister before the failure diagnosis is equal to or larger than the predetermined determination value. Accordingly the ECU does not execute the failure diagnosis. The required purge amount used for determining whether or not the failure diagnosis can be executed is determined according to the temperature before the failure diagnosis.

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.

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Toyota, Japan

Tokiji Ito