Nippondenso Co., Ltd.

Denso Corporation

Nippon Soken, Inc.

Yasuo Sagisaka

Yukihiro Yamashita

Toshio Kondo

Hisashi Iida

Masakazu Ninomiya

Akio Kobayashi

Yasuo Mukai

Masakazu Yamada

Masahiko Yamaguchi

Masahiko Tajima

Kuniaki Ueda

Jun Hasegawa

Kiyonori Sekiguchi

Masaaki Nakayama

Yasuo Hirata

Keisuke Itakura

Wakichi Kondo

Eijirou Yamada

Yoshihiko Hirata

Naofumi Fukue

Tetsuji Mitsuda

Ryuichi Sano

An electronic throttle control system has a throttle valve to be operated by an electric motor, and an electronic control unit for calculating a target opening degree of the throttle valve depending on a first preset vehicle speed desired by a vehicle driver, so that a vehicle is controlled to automatically run at the preset vehicle speed. When an external module, for example, an ACC module, is added to the electronic throttle control system, and a second preset vehicle speed is inputted from the external module to the electronic control unit the electronic, the electronic control unit selects one of the first and second preset vehicle speeds, which is lower than the other. Then, the target opening degree of the throttle valve is calculated based on the selected preset vehicle speed.

Control device for vehicle automatic running

In a multi-cylinder engine, to compute the air-fuel ratio of each cylinder by an air-fuel ratio sensor disposed in an exhaust pipe, a cylinder is determined by a crank angle detected by a crank angle sensor. A deviation in the air-fuel ratio of each cylinder is detected on the basis of the output signal of the air-fuel ratio sensor disposed in the exhaust pipe and the forcibly changed quantity of the air-fuel ratio.

Air-fuel ratio detection apparatus of internal combustion engine

An opening of a waste gate vale is adjusted to control an actual supercharging pressure of intake air. Abnormality in a changing characteristic of the actual supercharging pressure relative to a change in a TCV control duty value can be detected. When an engine is in a steady operation condition, the TCV control duty value is forcibly changed repeatedly by a predetermined amount from 0% to 100%. A deviation between a target supercharging pressure corresponding to the TCV control duty value and an actual supercharging pressure is calculated each time the TCV control duty value is changed by the predetermined amount. This deviation is compared with an abnormality determination value to determine presence/absence of the abnormality in the changing characteristic of the actual supercharging pressure relative to the change in the TCV control duty value.

Apparatus and method of abnormality diagnosis for supercharging pressure control system

A malfunction detection apparatus is disclosed for a forced induction system. The system includes a compressor provided on an upstream side of a throttle valve in an intake passage of an engine, an upstream intake pressure sensor that detects intake pressure between the compressor and the throttle valve, and an atmospheric pressure sensor that detects atmospheric pressure. The malfunction detection apparatus includes a malfunction detection program that makes a comparison between the atmospheric pressure detected by the atmospheric pressure sensor and the upstream intake pressure detected by the upstream intake pressure sensor. The comparison is made in an operating state of the forced induction system in which the compressor compresses an amount of air that is approximately equal to or less than a predetermined amount to thereby determine whether the upstream pressure sensor has a malfunction.

Malfunction detection apparatus for pressure sensor

In a cooling mechanism for an engine electronic control module, a base plate of the engine electronic control module is attached to an intake pipe, and includes air rectifier fins. The air rectifier fins have an air rectification function for concentrating suction-air streams at a position while rectifying the suction-air streams, and a cooling function for cooling the engine electronic control module. Suction air flows into an intake duct, in which an air flow meter is provided, through the air rectifier fins. Therefore, eddies of air can be restricted from being generated at an upstream side of the air flow meter, thereby obtaining stable air-flow signals from the air flow meter.

Cooling mechanism for engine electronic control module

An oxygen concentration detecting apparatus precisely and easily performs diagnosis of a limit current type oxygen sensor. The limit current type oxygen sensor has an oxygen concentration detecting element for outputting limit current proportional to the oxygen concentration and a heater for heating the detecting element. A CPU of a microcomputer controls energization of the heater to activate the oxygen sensor. The CPU calculates element resistance based on the voltage applied to the oxygen sensor and the current detected in the sensor. In a sensor diagnosis routine, the CPU determines whether preconditions for the diagnosis have been met. If all the preconditions have been met, the CPU executes the diagnosis. That is, the CPU determines whether the element resistance is within a predetermined range. If it is below the range, the CPU determines that the sensor has high element temperature abnormality. If the element resistance is above the range, the CPU determines that the sensor has low element temperature abnormality.

Oxygen concentration detecting apparatus

An air/fuel ratio control system controls the supply of fuel to an internal combustion engine to achieve a target air/fuel ratio, based on the output of an air/fuel ratio sensor. The system may determine whether there is an abnormality in the air/fuel ratio sensor based on a comparison between a change of an air/fuel ratio correction coefficient, used to drive the air/fuel ratio to the target value, and a change of the target air/fuel ratio if the target air/fuel ratio has sharply changed. Alternatively, the diagnosis operation may be performed based on a comparison between a total air/fuel ratio correction amount and a change of the air/fuel ratio detected by the air/fuel ratio sensor, a phase difference calculation between peaks of the air/fuel ratio or the air/fuel ratio correction coefficient, or by accumulating the differences between the air/fuel ratio and the target air/fuel ratio, and the differences between the air/fuel ratio correction coefficient and a reference value, and comparing the accumulated values. In addition, the system may detect a sensor abnormality based on the deviation in phase of the air/fuel ratio from the air/fuel ratio correction coefficient. These diagnosis operations can precisely and easily detect the occurrence of an abnormality in the air/fuel ratio sensor. As a result, the air/fuel ratio control system will not use an imprecise output from the sensor for air/fuel ratio control, thus achieving highly precise and highly reliable air/fuel ratio control.

Abnormality diagnosing system for air/fuel ratio feedback control system

The fuel ratio control system controls the supply of fuel to an internal combustion engine to achieve a target air-fuel ratio, based on the output of an air-fuel ratio sensor. The system may determine whether there is an abnormality in the air-fuel ratio sensor based on a comparison between a change of an air-fuel ratio correction coefficient, used to drive the air-fuel ratio to the target value, and a change of the target air-fuel ratio if the target air-fuel ratio has sharply changed. Alternatively, the diagnosis operation may be performed based on a comparison between a total air-fuel ratio correction amount and a change of the air-fuel ratio detected by the air-fuel ratio sensor, a phase difference calculation between peaks of the air-fuel ratio or the air-fuel ratio correction coefficent, or by accumulating the differences between the air-fuel ratio and the target air-fuel ratio, and the differences between the air-fuel ratio correction coefficient and a reference value, and comparing the accumulated values. In addition, the system may detect a sensor abnormality based on the deviation in phase of the air-fuel ratio from the air-fuel ratio correction coefficient. These system may also detect sensor abnormality on the basis of the behavior of the air-fuel ratio during transitional engine operation. As a result, the air-fuel ratio control system will not use an imprecise output from the sensor for air-fuel ratio control, thus achieving highly precise and highly reliable air-fuel ratio control.

Diagnostic apparatus for air-fuel ratio sensor

To appropriately detect malfunction of an air quantity adjusting valve in any type of case, an electronic control type throttle valve is disposed in an air intake pipe of an engine. An ISC valve which is duty controlled by an ECU is disposed in a bypass passage which bypasses the throttle valve. A CPU within the ECU establishes a drive duty ratio of the ISC valve to control engine speed in a target speed region during idling of the engine. Additionally, in a case where the drive duty ratio exceeds a predetermined control range (0 to 100%), the CPU controls idle speed by the throttle valve. Accordingly, in a case where throttle aperture is larger than a predetermined value TAH, or in a case where throttle aperture is smaller than a predetermined value TAL (where TAH&gt;TAL), the CPU determines that an opening side malfunction or a closing side malfunction has occurred in the ISC valve.

Malfunction diagnosis device for engine speed controller

A self-diagnostic apparatus of an air-fuel ratio control system of an internal combustion engine performs processes of starting the diagnostic process as the fuel-cut is started, reading and storing a sensor output at the start of the fuel-cut and counting an elapsed time after the start of the fuel-cut by actuating a timer, reading a time until when the sensor output rises from the start of the fuel-cut from the count value of the timer, calculating a rate of change of the sensor output and comparing the calculated rate of change with an abnormality determining value. When the rate of change is large, the response characteristic of the sensor is normal. When it is small, the response characteristic of the sensor is abnormal (degraded), so that the abnormality of the sensor is stored in a memory and an alarm lamp is lighted to inform a driver of the abnormality of the sensor.

Self-diagnostic apparatus of air-fuel ratio control system of internal

A device for controlling fuel injection of an internal combustion engine which is capable of preventing the A/F ratio from becoming over-rich immediately after the engine is started to decrease the emission of hydrocarbons. An intake pipe is connected to a four-cylinder spark ignition-type gasoline engine, and an injector for injecting fuel is disposed in the intake pipe for each of the cylinders of the engine. An electronic control unit (ECU) controls fuel injection through the injector in an amount corresponding to the running condition of the engine. When the number of revolutions of the engine reaches a predetermined value (e.g., 500 to 1000 rpm), the ECU judges that complete combustion has occurred and then decreases the amount of fuel injected through the injector during a period in which the amount of fuel adhered to the wall surfaces is excessive.

Device for controlling fuel injection of an internal combustion engine

In a combustion engine control, an amount of fuel suitable for each combustion cycle in the combustion engine is determined, the fuel is injected into the combustion engine, a spark for igniting the injected fuel is generated in the combustion engine, it is detected that the combustion engine is ordered to be stopped, the combustion engine is stopped by preventing to start injecting the fuel into the combustion engine after it is detected that the combustion engine is ordered to be stopped, the determined amount of fuel completes being injected into the combustion engine after the fuel starts to be injected into the combustion engine, regardless of whether it is detected that the combustion engine is ordered to be stopped.

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Komaki, Japan

Yasuo Sagisaka