A method for controlling a sudden unintended acceleration due to misoperation of an engine in a power split type hybrid electric vehicle (HEV) system, the method including when a determination is made that a delta revolution per minute (RPM) of an engine is out of a predetermined criterion, determining that an operating point of the engine does not move along a profile defined according to a target operating point of the engine and the sudden unintended acceleration is possible. The delta RPM is a difference of value between a current RPM of the engine and a profile RPM of the engine required to move to the target operating point of the engine from a current operating point of the engine.

The hybrid vehicle performs battery-less drive control to control an engine such that the engine is autonomously operated at an autonomous operation rotation speed, to control a first motor such that a torque based on a driving force required for a run of the hybrid vehicle is output from the first motor, and to control a second motor such that an electric power by subtracting an auxiliary machinery power from an electric power charged or discharged by the first motor is charged or discharged by the second motor. During the battery-less drive control, when a rotation speed of the engine becomes lower than a first predetermined rotation speed that is lower than the autonomous operation rotation speed, the hybrid vehicle performs torque adjustment control to decrease an absolute value of the torque output from the first motor.

The hybrid vehicle includes an engine, a motor connected to the engine, and an electronic control unit configured to control the motor to execute motoring to rotate a crankshaft of the engine. The electronic control unit is configured to execute speed-drop offset control when a rotation speed of the engine falls below a first rotation speed that is lower than a self-sustaining rotation speed of the engine while the engine is operated in a self-sustaining manner at the self-sustaining rotation speed.

A work vehicle includes an engine mounted on a traveling body including traveling wheels; a hydraulic stepless transmission that shifts a speed of the driving force from the engine; a gear shift pedal that performs an acceleration/deceleration operation of a shifted output from the hydraulic stepless transmission; and a control section that controls the engine and the hydraulic stepless transmission based on the operation amount of the gear shift pedal. When an operation on a set switch is received in a state where the gear shift pedal is pressed by a foot operation in an auto-cruise standby mode, the control section stores the vehicle speed and the number of engine revolutions in accordance with the foot operation position of the gear shift pedal and shifts to an auto-cruise mode.

Methods and systems are provided for reducing or avoiding engine hesitation and/or stall during engine idle conditions. In one example, a method may include inferring an engine idle condition, and in response, controlling a speed of an engine to a compensated engine idle speed that is a function of an extent to which a canister purge valve that regulates an amount of fluid flow to the engine from a fuel system and/or an evaporative emissions system, is degraded. In this way, an amount of fuel utilized to compensate for the degraded canister purge valve may be proportionate to the extent to which the canister purge valve is degraded.

Methods and systems are provided for reducing or avoiding engine hesitation and/or stall during engine idle conditions. In one example, a method may include inferring an engine idle condition, and in response, controlling a speed of an engine to a compensated engine idle speed that is a function of an extent to which a canister purge valve that regulates an amount of fluid flow to the engine from a fuel system and/or an evaporative emissions system, is degraded. In this way, an amount of fuel utilized to compensate for the degraded canister purge valve may be proportionate to the extent to which the canister purge valve is degraded.

A method of controlling speed of an internal combustion engine is disclosed. The method includes receiving a load parameter input. The method also includes determining a requested speed demand and detecting a change in load based on the load parameter input. The method also includes determining a modified speed demand based on the detected change in load, and modifying the requested speed demand to the modified speed demand.

The disclosure relates to a method for operating a motor vehicle that includes a drive unit, an output unit, and a clutch arranged between the drive unit and the output unit and configured to transmit a torque. A detection unit detects an operating state of the drive unit. When the operating state of the drive unit is in an overrun mode, a control unit controls a clutch slip, which results in adjustment of the torque that can be transmitted as a function of a speed of the motor vehicle. The disclosure further relates to a device for operating a motor vehicle, and to a motor vehicle that includes such a device.

A method for operating a hybrid vehicle includes monitoring, a rotational speed of an internal combustion engine (2) or a rotational speed of an electric machine (3) or a rotational speed of a transmission (4) or a rotational speed of a driven end (5) during travel with the internal combustion engine (2) running and the separating clutch (7) engaged in order to determine an increase in driving resistance. The method also includes, when the monitored rotational speed falls below or reaches a first limiting value, partially disengaging the separating clutch (7) toward a disengagement position in which a torque transmitted by the separating clutch (7) is adjusted such that an idling speed governor of the internal combustion engine (2) accelerates the rotational speed of the internal combustion engine toward the idling speed of the internal combustion engine (2).

A control arrangement for use in a drive arrangement of a vehicle includes an engine, a hydrostatic transmission, a load sensing means configured to detect a load on the engine, and an engine speed controller for controlling the engine. The arrangement further includes a pressure control means configured to act on a pressure in the hydrostatic transmission and a drive controller. The load sensing means generates a first signal, and based on the first signal, the drive controller generates a second signal for the engine speed controller and the pressure control means.