Abstract: In the event that an abnormality is detected in a throttle valve driving apparatus, an upper limit value for a throttle valve opening is set according to a vehicle speed when a brake switch is not switched on. When the brake switch is on, the upper limit value is set at a predetermined idle opening. When the target opening which is calculated according to an accelerator pedal depression amount is larger than the upper limit value, the target opening is changed to the upper limit value.

Abstract: A control system for an internal combustion engine having at least one intake valve and at least one exhaust valve is disclosed. The control system includes a valve operating characteristic varying mechanism and a hydraulic control valve for controlling a hydraulic pressure to be supplied to the valve operating characteristic varying mechanism. The valve operating characteristic varying mechanism continuously varies an operating phase of the at least one intake valve and/or the at least one exhaust valve of the engine. A cleaning operation of the hydraulic control valve is performed in a predetermined operating condition of the engine. An intake air amount of the engine is controlled according to an operating condition of the valve operating characteristic varying mechanism when the cleaning operation of the hydraulic control valve is performed.

Abstract: In a V-type engine in which two air supply pipes are connected to banks thereof, respectively, two air-fuel ratio sensors are provided at positions downstream of the air supply pipes for producing outputs corresponding to the density of oxygen in exhaust emissions. When exhaust secondary air is supplied, differences between air-fuel ratio feedback correction factors calculated based on outputs of two air-fuel ratio sensors at a time and air-fuel feedback correction factors calculated at a time that is a time that results after a predetermined period of time has elapsed since the time are calculated. The differences so calculated are compared with a predetermined value, and, when the calculated differences do not exceed the predetermined value, the exhaust secondary air supply system is detected to fail.

Abstract: There is provided a power output control system for an internal combustion engine, which enables the vehicle to smoothly perform refuge travel to find a place to park when an electric throttle control device becomes incapable of controlling a throttle valve, while ensuring adequate traveling performance. An ECU determines whether or not the electric throttle control device is incapable of controlling the throttle valve, and interrupts energization of the electric throttle control device when it is determined that the electric throttle control device is incapable of controlling the throttle valve. At this time, the opening of the throttle valve is held at the default opening degree by a spring. Further, basic ignition timing is calculated according to the engine rotational speed and load on the engine, and ignition timing of the engine is determined by correcting the calculated basic ignition timing according to the amount of operation of the accelerator pedal.

Abstract: There is provided a control system for a vehicle, which enables the vehicle to smoothly travel only to find a place to park when an electric throttle control device is in a condition incapable of controlling a throttle valve, thereby improving drivability. An ECU determines whether or not the electric throttle control device is in the condition incapable of controlling the throttle valve, and interrupts energization of the electric throttle control device when it is determined that the electric throttle control device is in the condition incapable of controlling the throttle valve. The throttle valve is held at a default opening position by a spring when the electric throttle control device is determined to be in the condition incapable of controlling the throttle valve. A throttle valve opening sensor detects a degree of opening of the throttle valve.

Abstract: In the event that an abnormality is detected in a throttle valve driving apparatus, an upper limit value for a throttle valve opening is set according to a vehicle speed when a brake switch is not switched on. When the brake switch is on, the upper limit value is set at a predetermined idle opening. When the target opening which is calculated according to an accelerator pedal depression amount is larger than the upper limit value, the target opening is changed to the upper limit value.

Abstract: A control system for an internal combustion engine having at least one intake valve and at least one exhaust valve is disclosed. The control system includes a valve operating characteristic varying mechanism and a hydraulic control valve for controlling a hydraulic pressure to be supplied to the valve operating characteristic varying mechanism. The valve operating characteristic varying mechanism continuously varies an operating phase of the at least one intake valve and/or the at least one exhaust valve of the engine. A cleaning operation of the hydraulic control valve is performed in a predetermined operating condition of the engine. An intake air amount of the engine is controlled according to an operating condition of the valve operating characteristic varying mechanism when the cleaning operation of the hydraulic control valve is performed.

Abstract: There is provided a power output control system for an internal combustion engine, which enables the vehicle to smoothly perform refuge travel to find a place to park when an electric throttle control device becomes incapable of controlling a throttle valve, while ensuring adequate traveling performance. An ECU determines whether or not the electric throttle control device is incapable of controlling the throttle valve, and interrupts energization of the electric throttle control device when it is determined that the electric throttle control device is incapable of controlling the throttle valve. At this time, the opening of the throttle valve is held at the default opening degree by a spring. Further, basic ignition timing is calculated according to the engine rotational speed and load on the engine, and ignition timing of the engine is determined by correcting the calculated basic ignition timing according to the amount of operation of the accelerator pedal.

Abstract: There is provided a control system for a vehicle, which enables the vehicle to smoothly travel only to find a place to park when an electric throttle control device is in a condition incapable of controlling a throttle valve, thereby improving drivability. An ECU determines whether or not the electric throttle control device is in the condition incapable of controlling the throttle valve, and interrupts energization of the electric throttle control device when it is determined that the electric throttle control device is in the condition incapable of controlling the throttle valve. The throttle valve is held at a default opening position by a spring when the electric throttle control device is determined to be in the condition incapable of controlling the throttle valve. A throttle valve opening sensor detects a degree of opening of the throttle valve.

Abstract: There is provided a valve timing control system for an internal combustion engine, which is capable of enhancing the accuracy of valve timing control. The valve timing control system 1 for the internal combustion engine 3 changes the cam phase of an intake cam 6a relative to a crankshaft 9, to thereby control the valve timing of an intake valve 4. The valve timing control system 1 fixes a desired cam phase CAINCMD at a value CAINCMDFC during an fuel cut-off, and controls a cam phase change mechanism 8 such that from a time t2 during the fuel cut-off, the cam phase is held at a value assumed at the time t2. Further, the valve timing control system 1 calculates a learned value DCALEARN of the amount of deviation of an actual cam phase CAIN based on a plurality of values of the actual cam phase CAIN detected at and after the time t2, and the constant value CAINCMDFC of the desired cam phase CAINCMD (step S5).

Abstract: There is provided a valve timing control system for an internal combustion engine, which is capable of properly setting the reference position of the cam phase by learning, and at the same time promptly establishing a learned value of the reference position when the learned value is lost, thereby accurately changing the cam phase for proper control of the valve timing of the engine. A cam phase change mechanism changes the cam phase. A reference value indicative of a reference position of the cam phase is learned at a predetermined learning speed based on the cam phase detected when the cam phase change mechanism is in a predetermined operative state, and the learned reference value (learned value) is stored in a RAM. When the loss of the learned value from the RAM is detected, a learning speed at the reference value is learned is corrected such that the learning speed is increased from the predetermined learning speed for a predetermined time period.

Abstract: There is provided a valve timing control system for an internal combustion engine, which is capable of properly setting the reference position of the cam phase by learning, and at the same time promptly establishing a learned value of the reference position when the learned value is lost, thereby accurately changing the cam phase for proper control of the valve timing of the engine. A cam phase change mechanism changes the cam phase. A reference value indicative of a reference position of the cam phase is learned at a predetermined learning speed based on the cam phase detected when the cam phase change mechanism is in a predetermined operative state, and the learned reference value (learned value) is stored in a RAM. When the loss of the learned value from the RAM is detected, a learning speed at the reference value is learned is corrected such that the learning speed is increased from the predetermined learning speed for a predetermined time period.

Abstract: There is provided a valve timing control system for an internal combustion engine, which is capable of enhancing the accuracy of valve timing control. The valve timing control system 1 for the internal combustion engine 3 changes the cam phase of an intake cam 6a relative to a crankshaft 9, to thereby control the valve timing of an intake valve 4. The valve timing control system 1 fixes a desired cam phase CAINCMD at a value CAINCMDFC during an fuel cut-off, and controls a cam phase change mechanism 8 such that from a time t2 during the fuel cut-off, the cam phase is held at a value assumed at the time t2. Further, the valve timing control system 1 calculates a learned value DCALEARN of the amount of deviation of an actual cam phase CAIN based on a plurality of values of the actual cam phase CAIN detected at and after the time t2, and the constant value CAINCMDFC of the desired cam phase CAINCMD (step S5).

Abstract: A secondary air supply control system controls supply of air to a catalyst arranged in the exhaust passage of an internal combustion, for purification of exhaust gases. A temperature difference between a temperature of an engine coolant sensed at a stoppage of the engine and stored and a temperature of the engine coolant sensed at a start of the engine after the stoppage is calculated. It is determined whether or not a stop time period between the stoppage and the start of the engine is short, depending on the temperature difference. When it is determined that the stop time period is short, an operation time period over which the air pump is to be operated to supply air to the catalyst is corrected based on a temperature difference between a temperature of the engine coolant sensed at the start of the engine and a temperature of intake air sensed at the start of the engine.

Abstract: An evaporative fuel control system for an internal combustion engine having a throttle valve includes a canister for adsorbing evaporative fuel generated in the fuel tank, a purging passage for purging evaporative fuel into the intake system of the engine, and a purge control valve for controlling a flow rate of the evaporative fuel to be purged into the intake system through the purging passage. An ECU sets an air-fuel ratio correction coefficient applied in air-fuel ratio feedback control, based on the concentration of a specific component in exhaust gases emitted from the engine, calculates a first learned value of the air-fuel ratio correction coefficient during execution of the air-fuel ratio feedback control, and controls the purge control valve such that the flow rate of the evaporative fuel is changed according to the calculated first learned value. A second learned value of the air-fuel ratio correction coefficient suitable for the transient operating condition of the engine is calculated.

Abstract: A fuel supply control system for an internal combustion engine installed in a vehicle controls fuel supply to the engine such that supply of fuel to the engine is interrupted when the rotational speed of the engine exceeds a first predetermined value, and the supply of fuel to the engine is resumed when the rotational speed of the engine decreases a second predetermined value which is lower than the first predetermined value. The first predetermined value is decreased when the temperature of the engine exceeds a predetermined value over a predetermined time period. The operation of at least one of accessories of the vehicle is interrupted when the first predetermined value is decreased.

Abstract: Disclosed is a control device for internal-combustion engine which is capable of detecting an abnormality in accelerator pedal angle sensors throughout a range of accelerator pedal angles and continuing operation even when an abnormality is detected. It includes a first accelerator pedal angle sensor for detecting an accelerator pedal angle, a second accelerator pedal angle sensor for detecting the accelerator pedal angle, and a minor selection device for selecting, as the accelerator pedal angle, a lower value of one of the outputs of the first accelerator pedal angle sensor and the second accelerator pedal angle sensor.

Abstract: An electronic control apparatus for an engine of a vehicle has a first CPU for fuel control which controls the amount of fuel to be supplied to the engine and a second CPU for throttle valve control which outputs a driving signal to an actuator which operates to open or close the throttle valve disposed in an intake pipe to the engine. The apparatus has an opening degree computing member which is provided in the first CPU to compute an opening degree of the throttle valve based at least on an amount of depression of an accelerator and then to output a result thereof as an opening degree signal. The first CPU and the second CPU are connected together by a communication line which transfers the opening degree signal from the opening degree computing member from the first CPU to the second CPU.

Abstract: An apparatus of controlling an intake air throttle valve capable of obtaining the certain drive for the change in the load applied to the throttle valve due to the change in the intake air amount in the transient period, without any increase in current consumption and reduction in responsiveness. The apparatus includes a throttle valve for controlling an intake air amount in the internal combustion engine; a motor for electrically controlling the throttle valve; and a drive circuit for controlling the drive torque of the motor. It further includes a throttle valve opening defining device for defining a parameter indicating the opening of the throttle valve; a comparing device for comparing the value of the parameter defined by the throttle valve opening defining device; and a torque increasing device for increasing the output torque by the drive circuit when the comparing device judges that the value of the parameter is larger than the specified value.

Abstract: Disclosed is a fuel supply control device which can properly control fuel supply at any time by recovering within a short time in the event of out of phase in the drive of the step motor.