Honda Giken Kogyo Kabushiki Kaisha

Honda Giken Kogyo K.k.

Yoshitaka Hibino

Takeshi Fukuzawa

Atsushi Totsune

Masahiko Asakura

Hiromitsu Sato

Hiroshi Kogure

Hiroyuki Sugiura

Norimitsu Kurihara

Toshikazu Oketani

Hiroshi Hasebe

Shinichi Kubota

Akira Hashimoto

Hiroshi Ikura

Takefumi Hosaka

Syunzaburo Ozaki

Akira Kikuchi

Hiroshi Goto

Kentaro Yokoo

Koji Kajita

Masaaki Tomii

Satoru Kubo

Takeshi Kijima

Kogi Kajita

In an exhaust secondary air supply system including an electric air pump and a flow rate control valve disposed in an air supply passage connected to an exhaust passage of an engine, the electric air pump is first driven after the start of the engine, and the flow rate control valve is then opened after a lapse of a predetermined time. At a time after starting the driving of the electric air pump, the abnormality of the electric air pump is detected by comparing a deviation between the current before and after driving of the electric air pump with a predetermined reference value. After opening of the flow rate control valve, the abnormality of the flow rate control valve is detected by comparing the deviation between the current before and after the opening of the flow rate control valve with a predetermined reference value.

Abnormality detecting device for exhaust secondary air supplying system

A method of controlling the air-fuel ratio of a mixture being supplied to an internal combustion engine, in a feedback manner responsive to an output signal from an O.sub.2 sensor arranged in the engine exhaust system for sensing the concentration of a component in exhaust gases from the engine to produce as the output signal a normally fluctuating output signal indicative of the concentration. The air-fuel ratio is controlled to a desired value by means of at least one of proportional control applying a first correction value to correct the air-fuel ratio when the output signal changes from a rich side to a lean side or vice versa with respect to a predetermined reference value, and integral control applying a second correction value to correct the air-fuel ratio whenever a predetermined period of time elapses so long as the output signal remains on the lean side or on the rich side with respect to the predetermined reference value. A correcting amount is determined in response to the rate of change in the output signal of the O.sub.2 sensor. The second correction value is to be increased or decreased by means of the correcting amount, depending upon whether the output signal remaining on the lean side or on the rich side.

Air-fuel ratio feedback control method for internal combustion engines

An apparatus for detecting a neutral state of a transmission gear of a vehicle detects an engine rotational speed, a vehicle speed, and a condition in which the engine output power is transmitted to the transmission gear through a clutch. The apparatus judges that the transmission gear is in the neutral state when a ratio between the engine rotational speed and the vehicle speed is in any one of predetermined ranges. The apparatus also judges that the transmission gear is in the neutral state when a variation of the ratio between the engine rotational speed and the vehicle speed within a predetermined time period is greater than a predetermined value.

Apparatus for detecting a neutral state of a transmission gear of a

A controlled system for the clutch in a torque converter of an automatic transmission wherein the clutch is normally engaged in a predetermined range of vehicle and engine operating conditions for efficient operation. An atmospheric pressure sensor is used in the control system to disengage the clutch in that predetermined range at higher altitudes to allow the torque converter to function to increase the torque being transmitted thereby compensating for the reduced engine performance at higher altitudes.

Clutch operation control system for fluid torque converter of vehicular

A method of detecting abnormality in an air-fuel ratio control system for an internal combustion engine, the air-fuel ratio control system having a proportional control valve arranged in an air supply passage for supplying secondary air therethrough to the engine and controlled in response to an output signal from an oxygen concentration sensor arranged in an exhaust system of the engine in a manner such that its valve opening varies in proportion to the magnitude of driving current supplied thereto. A circuit is provided which includes a first transistor, the proportional control valve, and a second transistor arranged in the order mentioned and serially connected with each other between a power source for supplying a predetermined voltage and ground. A value of voltage at a predetermined location in said circuit is sensed while the first and second transistors are in predetermined states of conduction and non-conduction. It is determined whether there is abnormality in the air-fuel ratio control system, on the basis of the sensed voltage value.

Abnormality detecting method for air-fuel ratio control system for

A temperature of an internal combustion engine is sensed when the engine is started and elapsed time from engine start is also sensed. Engine intake air temperature is estimated on the basis of the sensed engine temperature and sensed elapsed time. The operation of the engine is controlled in accordance with the estimated engine intake air temperature.

Method of controlling operation of internal combustion engines in

The invention is provided with a load detecting means for detecting the value of an electric load connected to an electric generator driven by an internal combustion engine. An idling speed-up means stepwise increases an idling speed of the engine. A control means causes the idling speed-up means to operate when the detected value of the electric load continuously remains above a predetermined value for a predetermined length of waiting time. The control means is provided with a variable setting means which variably sets the waiting time in such a manner that the larger the detected value of the electric load, the shorter the length of the waiting time.

Idling speed-up control apparatus internal combustion engine

In a method for determining a control parameter of an air/fuel ratio control system of an internal combustion engine by means of an oxygen concentration sensor disposed in an exhaust system of the engine, the control parameter of the air/fuel ratio is determined independently of the output signal of the oxygen concentration sensor when a light load operation of the engine continued for more than a predetermined time period is detected.

Control method of controlling an air/fuel ratio control system in an

While an exhaust gas sensor having an output characteristic linear with respect to the concentration of a specific component in exhaust gases from an internal combustion engine, the opening of an automatic choke valve is controlled in response to the degree of warming-up of the engine. From the time of activation of the exhaust gas sensor to the time of completion of warming-up of the engine, the automatic choke valve and an air-fuel ratio control valve arranged in an air passage bypassing a throttle valve in an intake passage of the engine, are driven so as to achieve a desired air-fuel ratio, respectively, when the difference between the desired air-fuel ratio and actual one is larger than a predetermined value, and when the difference is smaller than the predetermined value. After completion of warming-up of the engine, the air-fuel ratio control valve is driven in response to operating conditions of the engine so as to achieve the desired air-fuel ratio.

Air-fuel ratio control system for internal combustion engines capable of

An exhaust gas recirculation method which controls the valve opening of an exhaust gas recirculating valve to values appropriate to operating conditions of an automotive vehicle and an internal combustion engine installed therein, to thereby regulate the amount of exhaust gas recirculated from an exhaust passage to an intake passage in the engine. It is determined whether the vehicle is in a predetermined starting condition, and the valve opening of the exhaust gas recirculating valve is set to a first value when the vehicle is not in the predetermined starting condition, otherwise to a second value smaller than the first value. Preferably, the determination of whether the vehicle is in the predetermined starting condition is made based on the rotational speed of the engine and the speed of the vehicle.

Exhaust gas recirculation method for internal combustion engines for

An air/fuel ratio control system is constructed to calculate a base value of an air/fuel ratio control in response to a plurality of engine operational parameters. The base value is adjusted by an output signal of an exhaust gas component concentration sensor, to provide an output value which is directly used for the air/fuel ratio control. Under a predetermined operational condition of the engine, the adjustment of the base value on the basis of the output signal of the exhaust gas component concentration sensor is stopped and the base value is corrected by a correction value, which is one of a number of values stored correspondingly as engine operational parameters, and read out using present values of the engine operational parameters.

Air fuel ratio control system for an internal combustion engine with an

A method for indicating a vehicle operation in a fuel economy range, for a vehicle with a manual transmission, indicates that the vehicle is operating in a fuel economy range when both of an up-shifting condition and a down-shifting condition are not satisfied. The method further detects a non-regular state of the vehicle operation and stops the indication of the vehicle operation under the fuel economy range when the non-regular state of the vehicle operation is detected even though both of the up-shifting and down-shifting conditions are not satisfied.

Method for indicating a vehicle operation in a fuel economy range for a

A method determines a control parameter of an air/fuel ratio of an internal combustion engine having an idle rotational speed control device by which the throttle valve is opened when an electric unit such as the head light or the air conditioner is turned on during the idling of the engine. The air/fuel ratio is controlled to be leaner than a target air fuel ratio when the engine is idling, and controlled to a further leaner side when the electric unit is operating during the idling of the engine.

Method of controlling an air/fuel ratio of a vehicle mounted internal

A method for indicating a running condition of a vehicle having an engine and a manual transmission generates a direction of a down-shift operation according to a detected opening angle of a throttle valve of the engine and detected acceleration and deceleration of the vehicle. The direction of the down-shift operation is generated when the acceleration of the vehicle is above a predetermined value while the throttle valve is substantially fully closed and when the deceleration of the vehicle is above a predetermined value while the throttle valve is substantially fully opened. Thus, a suitable direction of gear position is generated when the vehicle is climbing an uphill road or coasting on a downhill road.

Method for directing a down-shift operation for a vehicle with a manual

An air intake side secondary air supply system for an internal combustion engine is provided with a device for restricting the amount of the secondary air flowing through an air intake side secondary air supply passage when an amount of an intake air of the engine is small. By the provision of the flow restriction device, the operating range of an open-close valve or a linear type solenoid valve which is provided for controlling the air intake side secondary air, in which range the linearity of the operation of the valve is good, can be always used. Thus, the accuracy of the air/fuel ratio control is improved especially when the amount of the intake air of the engine is small.

Growing community of inventors

Wako, Japan

Yoshitaka Hibino