An engine control apparatus includes a throttle valve, an accelerator opening detector, a throttle opening controller, and an intake air density detector. The throttle valve is configured to regulate an intake air volume of an engine. The accelerator opening detector is configured to detect an accelerator opening that is an operation amount of an accelerator operation member with which a driver operates an accelerator. The throttle opening controller is configured to increase a throttle opening of the throttle valve in accordance with an increase in the accelerator opening. The intake air density detector is configured to detect information about an intake air density of the engine. In a low intake air density state where the intake air density is a predetermined value or lower, the throttle opening controller decreases a sensitivity of the throttle opening relative to the accelerator opening in a partial range of a range where the accelerator opening is variable.

A control system for a fuel cutoff system of a motor vehicle includes a fuel cutoff module that generates a fuel cutoff signal for disabling a supply of fuel to an engine, in response to the fuel cutoff module detecting a deceleration fuel cutoff (DFCO) event. The control system further includes an oxygen storage module determining an amount of oxygen accumulated in a catalyst and comparing this amount to an oxygen storage capacity (OSC) of the catalyst, in response to the fuel cutoff module determining the DFCO event. The control system further includes an intake valve timing module generating a phasing signal to actuate a plurality of cam phasers to reduce a flow rate of oxygen to the catalyst, in response to the fuel cutoff module determining the DFCO event and the oxygen storage module determining that the amount of oxygen stored in the catalyst is less than the OSC.

A control system for a fuel cutoff system of a motor vehicle includes a fuel cutoff module that generates a fuel cutoff signal for disabling a supply of fuel to an engine, in response to the fuel cutoff module detecting a deceleration fuel cutoff (DFCO) event. The control system further includes an oxygen storage module determining an amount of oxygen accumulated in a catalyst and comparing this amount to an oxygen storage capacity (OSC) of the catalyst, in response to the fuel cutoff module determining the DFCO event. The control system further includes an intake valve timing module generating a phasing signal to actuate a plurality of cam phasers to reduce a flow rate of oxygen to the catalyst, in response to the fuel cutoff module determining the DFCO event and the oxygen storage module determining that the amount of oxygen stored in the catalyst is less than the OSC.

An engine control apparatus includes a throttle valve, an accelerator opening detector, a throttle opening controller, and an intake air density detector. The throttle valve is configured to regulate an intake air volume of an engine. The accelerator opening detector is configured to detect an accelerator opening that is an operation amount of an accelerator operation member with which a driver operates an accelerator. The throttle opening controller is configured to increase a throttle opening of the throttle valve in accordance with an increase in the accelerator opening. The intake air density detector is configured to detect information about an intake air density of the engine. In a low intake air density state where the intake air density is a predetermined value or lower, the throttle opening controller decreases a sensitivity of the throttle opening relative to the accelerator opening in a partial range of a range where the accelerator opening is variable.

When a required pressure ratio RP* is less than or equal to a calculation switching pressure ratio RPwot, an engine control unit calculates, as a target opening degree TA*, a throttle opening degree TA at which a throttle upstream-downstream pressure ratio RP is the required pressure ratio RP*. When the required pressure ratio RP* exceeds the calculation switching pressure ratio RPwot, the engine control unit obtains a switching point opening degree TAwot, a switching point load factor KLwot and a maximum load factor KLmax, and calculates the target opening degree TA* as a value that has a linear relationship with the required load factor KL* between the switching point opening degree TAwot and the maximum opening degree TAmax.

A control method for an internal combustion engine including: setting a target valve opening degree of the first throttle valve in accordance with a load, sensing a valve opening degree of the second throttle valve, judging whether or not the valve opening degree of the second throttle valve is an opening degree on a closing side relative to a predetermined set valve opening degree, and correcting the valve opening degree of the first throttle valve to the opening degree on the closing side relative to the target valve opening degree when it is judged that the valve opening degree of the second throttle valve is the opening degree on the closing side relative to the predetermined set valve opening degree.

An electronic governor system includes a motor, a transmission coupled to the motor, a throttle plate coupled to the transmission, the throttle plate movable to multiple positions between closed and wide-open, wherein power is supplied to the motor to move the throttle pate to a desired position and wherein power is not supplied to the motor to maintain the throttle plate in the desired position.

A throttle control method of controlling an opening degree of a throttle valve in a multi-cylinder engine that includes throttle valves in intake passages provided for each cylinder. It is possible to independently control the opening degree for each of the throttle valves. The throttle control method includes controlling the opening degree of the throttle valve is based on differences among intake air amounts in the respective intake passages.

A system includes an electronic fuel injection system of an engine, the electronic fuel injection system including an electronic governor control unit for controlling various functions of the engine.

A throttle valve abnormality determination device includes a permission/rejection determination unit configured to determine whether or not to permit a sticking determination of a throttle valve. The determination unit is configured to prohibit the sticking determination if a first temperature, which is a temperature in a passage through which intake air flows, is less than or equal to a freezing temperature at which the throttle valve may be frozen when an engine is started and, after prohibiting the sticking determination, permit the sticking determination if an integrated value of a heat amount conversion value based on a second temperature, which is a temperature in the passage, and an intake air amount exceeds a threshold value when the second temperature is greater than or equal to a de-freezing temperature at which a frozen portion of the throttle valve is de-frozen.