Methods and systems are provided for an engine. In one example, a method comprises stopping an engine via a soft-stop method in response to a likelihood of condensate forming being less than or equal to a threshold likelihood. The method further comprises stopping the engine via an exhaust gas evacuation method in response to the likelihood of condensate forming being greater than the threshold likelihood.

A spark ignition type engine enabling engine startability to be favorable is provided. The spark ignition type engine includes a main intake-air passage; a throttle valve of the main intake-air passage; a bypass intake-air passage bypassing the throttle valve; an ISC valve of the bypass intake-air passage; and an electronic control device that controls an engine speed by adjusting an opening degree of the ISC valve, in which when the engine is started, cranking is performed at a cranking opening degree at which the ISC valve is narrowed by a predetermined amount from a fully opened state by control of the electronic control device, so that an intake-air negative pressure is generated on an intake-air downstream side of the ISC valve.

Methods and systems are provided for controlling a boosted engine system, having a turbocharger and a charge air cooler, to limit overheating of a compressor outlet. In one example, a method includes predicting an engine torque profile based on current and future engine operating conditions. The method then models a compressor outlet temperature profile and reduces engine torque output to limit overheating of the compressor outlet.

A spark ignition type engine enabling engine startability to be favorable is provided. The spark ignition type engine includes a main intake-air passage; a throttle valve of the main intake-air passage; a bypass intake-air passage bypassing the throttle valve; an ISC valve of the bypass intake-air passage; and an electronic control device that controls an engine speed by adjusting an opening degree of the ISC valve, in which when the engine is started, cranking is performed at a cranking opening degree at which the ISC valve is narrowed by a predetermined amount from a fully opened state by control of the electronic control device, so that an intake-air negative pressure is generated on an intake-air downstream side of the ISC valve.

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.

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.

Methods and systems are provided for controlling a boosted engine system, having a turbocharger and a charge air cooler, to limit overheating of a compressor outlet. In one example, a method includes predicting an engine torque profile based on current and future engine operating conditions. The method then models a compressor outlet temperature profile and reduces engine torque output to limit overheating of the compressor outlet.

A garden tool includes a gasoline engine and a power source, the gasoline engine including a fuel supply system and an ignition system. The garden tool may further include a control system with at least one sensor used for collecting a working condition signal of the gasoline engine and a controller used for receiving the working condition signal and controlling the fuel supply system and/or the ignition system according to the working condition signal received. The power source may provide a power supply for the fuel supply system, the ignition system, and the control system through the controller.

Methods and systems are provided for indicating whether a wastegate positioned in a vehicle exhaust system is stuck in a closed or open configuration. In one example, a method comprises activating an electric air compressor positioned in an intake of the engine and obtaining a first baseline air flow and a second baseline air flow in the exhaust system, and in response to an indication that the wastegate is potentially stuck open or closed, obtaining a test air flow measurement via activating the electric air compressor and comparing the test air flow in the exhaust system to the first and/or the second baseline air flow. In this way, the wastegate may be diagnosed under conditions of limited engine operation, such as that which may occur in hybrid electric vehicles.

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.