A spark ignition type engine adjusts a base lower limit value of a valve opening degree of an ISC valve to avoid excessive engine rotation that may occur when an increase correction by atmospheric pressure is performed. When a detected engine temperature becomes lower, the base lower limit value of the ISC valve opening degree is increased to the fully open side, and the base lower limit value is corrected to increase to the fully open side with an increase correction value on the basis of a detected atmospheric pressure in an engine middle-high temperature range where the engine temperature exceeds a predetermined value, and the increase correction value is increased to the fully open side as the detected atmospheric pressure becomes lower, and the increase correction is prohibited in an engine low temperature range where the engine temperature is equal to or lower than the predetermined value.

A spark ignition type engine adjusts a base lower limit value of a valve opening degree of an ISC valve to avoid excessive engine rotation that may occur when an increase correction by atmospheric pressure is performed. When a detected engine temperature becomes lower, the base lower limit value of the ISC valve opening degree is increased to the fully open side, and the base lower limit value is corrected to increase to the fully open side with an increase correction value on the basis of a detected atmospheric pressure in an engine middle-high temperature range where the engine temperature exceeds a predetermined value, and the increase correction value is increased to the fully open side as the detected atmospheric pressure becomes lower, and the increase correction is prohibited in an engine low temperature range where the engine temperature is equal to or lower than the predetermined value.

Systems and methods for operating an engine with deactivating and non-deactivating valves are presented. In one example, a position of an engine air intake throttle is adjusted during cylinder deactivation to control intake manifold pressure for cylinder reactivation. Closing of the throttle may be timed based on an actual total number of cylinder induction events expected to provide a desired engine intake manifold pressure.

Systems and methods for operating an engine with deactivating and non-deactivating valves are presented. In one example, a position of an engine air intake throttle is adjusted during cylinder deactivation to control intake manifold pressure for cylinder reactivation. Closing of the throttle may be timed based on an actual total number of cylinder induction events expected to provide a desired engine intake manifold pressure.

A control device estimates a leakage gas amount with respect to gas that leaks to an upstream side from a downstream side of a fresh air introduction valve when the fresh air introduction valve is closed. If the leakage gas amount is equal to or greater than a predetermined value when there is a request to open the fresh air introduction valve, a target opening degree of the fresh air introduction valve is determined based on the engine speed and intake pressure, and also a correction opening degree with respect to the target opening degree is calculated based on the leakage gas amount. The fresh air introduction valve is opened to an opening degree greater than the target opening degree by an amount corresponding to the correction opening degree, to thereby cause leakage gas that is accumulated in a fresh air introduction passage to flow into an intake passage together with a required amount of fresh air.

A throttle drive actuator for an engine includes a rotor and a stator. The rotor connects with a valve of a throttle body to rotate the valve, to open a close an air passage of the throttle body of the engine.

A throttle operating device includes a fixing member, a throttle lever, the throttle lever, a magnet which is configured to rotate in response to a rotational operation of the throttle lever, and a detection sensor. A drive source of the vehicle is configured to be controlled based on the rotational operation angle of the throttle lever detected by the detection sensor. A magnetic shielding unit is disposed in the fixing member and configured to cover a periphery of the magnet and the detection sensor to shield magnetism from the outside.

A throttle operating device includes a fixing member, a throttle lever, the throttle lever, a magnet which is configured to rotate in response to a rotational operation of the throttle lever, and a detection sensor. A drive source of the vehicle is configured to be controlled based on the rotational operation angle of the throttle lever detected by the detection sensor. A magnetic shielding unit is disposed in the fixing member and configured to cover a periphery of the magnet and the detection sensor to shield magnetism from the outside.

A transmission mechanism includes: an intermediate shaft secured to a support portion provided in a valve body of an electric throttle valve and disposed in parallel to a motor shaft and a valve shaft; and an intermediate gear rotatably disposed at the intermediate shaft, in which the intermediate gear has a first intermediate gear engaged with a motor gear secured to the motor shaft and a second intermediate gear engaged with a valve gear secured to the valve shaft, the first intermediate gear and the second intermediate gear are integrally configured to be aligned in an axial direction of the intermediate shaft, a hemispherical recessed portion recessed upward around an axial center of the intermediate shaft is formed at a lower end portion of the intermediate gear, and a projecting portion projecting upward in a hemispherical shape around the axial center of the intermediate shaft and supporting the recessed portion is formed in a surface of the support portion facing the recessed portion of the intermediate gear.

A transmission mechanism includes: an intermediate shaft secured to a support portion provided in a valve body of an electric throttle valve and disposed in parallel to a motor shaft and a valve shaft; and an intermediate gear rotatably disposed at the intermediate shaft, in which the intermediate gear has a first intermediate gear engaged with a motor gear secured to the motor shaft and a second intermediate gear engaged with a valve gear secured to the valve shaft, the first intermediate gear and the second intermediate gear are integrally configured to be aligned in an axial direction of the intermediate shaft, a hemispherical recessed portion recessed upward around an axial center of the intermediate shaft is formed at a lower end portion of the intermediate gear, and a projecting portion projecting upward in a hemispherical shape around the axial center of the intermediate shaft and supporting the recessed portion is formed in a surface of the support portion facing the recessed portion of the intermediate gear.