There is provided a vehicle-mounted control device that, when a restart request is generated during a time interval between the fulfillment of an engine automatic stop condition and complete stop, decreases a charging efficiency of an engine by means of at least one of a throttle valve and an intake valve to prevent an increase in the reverse rotational frequency of the engine, thereby ensuring the durability of the starting device of the engine, and preventing an accelerator response from deteriorating when a restart request based on the accelerator operation is generated. In the vehicle-mounted control device that controls a charging efficiency of the engine on the basis of the requested engine output amount, the engine is automatically stopped when a predetermined automatic stop condition is fulfilled, and a charging efficiency at the time when a restart condition of the engine has been fulfilled on the basis of an engine output request generated during a time interval between the fulfillment of the automatic stop condition and complete stop of the engine is made lower than a charging efficiency for the requested engine output amount.

Disclosed is a method for estimating a physical stoppage of an engine of a motor vehicle, subject to bounce-back, a target equipped with teeth being borne by the crankshaft and successive passes of the teeth past a sensor being detected, a first time count incrementing since a last detection of the passing of a tooth and being associated with a first time threshold with the first count being reset to zero when the time between passes of two successive teeth is below the first threshold. A second count associated with a second time threshold is performed, with this count being suspended when and for as long as a time between the passes of two successive teeth is below the second threshold, the engine being estimated to have stopped as soon as the counts have respectively reached the first and second thresholds.

If an internal combustion engine that has been automatically stopped is to be restarted under a decreased engine speed, a control unit of the internal combustion engine starts cranking when a crank angle of a cylinder in compression stroke of the internal combustion engine is closer to bottom dead center than a threshold value set in advance. More specifically, if an engine speed of the internal combustion engine is in forward rotation, the cranking is begun when the crank angle of the cylinder in compression stroke is closer to the bottom dead center than a threshold value set in advance. If the engine speed of the internal combustion engine is in backward rotation, the cranking is begun when the crank angle of the cylinder in compression stroke is closer to the bottom dead center than another threshold value set in advance.

An internal combustion engine comprises at least one cylinder, at least one cylinder head connected to at least one cylinder, at least one piston disposed in the at least one cylinder, a crankshaft operatively connected to the at least one piston, a crankcase housing at least a portion of the crankshaft, a motor-generator operatively connected to the crankshaft, a recoil starter operatively connected to the crankshaft, and a drive pulley of a continuously variable transmission (CVT) operatively connected to the crankshaft, the motor-generator. The recoil starter, the crankshaft and the drive pulley are coaxial. The motor-generator operates in motor mode to rotate the crankshaft and in generator mode to generate electricity.

An engine control device includes an electronic control unit. The electronic control unit is configured to perform a spark discharge with an ignition plug for each cylinder by cutting off energization after elapse of a predetermined period from start of energization to an ignition coil for each cylinder of the engine, to stop the spark discharge caused by the ignition plug for each cylinder after supply of fuel to the engine is stopped when operation of the engine is stopped, and to control an ignition plug so as to stop the spark discharge caused by the ignition plug from a cylinder after a rotation speed of a crankshaft decreases gradually and the rotation speed of the crankshaft reaches a preset threshold value or less, after the stop of the supply of fuel to the engine.

A system for starting an engine of a vehicle has a fuel injector injecting fuel into a closed intake port to form an air fuel mixture. The system also includes an actuator rotating a crankshaft in a first direction to open the intake port by moving a piston within a cylinder coupled to the crankshaft. A combustion chamber defines between the cylinder and the port receiving the air fuel mixture through the intake port. The actuator rotates the crankshaft in a second direction to close the intake port. A spark plug ignites the air fuel mixture to start the engine. The engine also includes many other disclosed features.

An engine synchronization method may include: detecting teeth numbers of crank teeth installed on a crankshaft based on a pulse signal generated from a crankshaft position sensor; calculating a tooth period between a falling edge and a next falling edge of the pulse signal generated from the crankshaft position sensor and detecting a missing tooth based on the calculated tooth period; determining whether the detected missing tooth is an actual missing tooth based on a tooth number detected at the time of detecting the missing tooth; and performing synchronization control of an engine when it is determined that the detected missing tooth is the actual missing tooth.

In response to a restarting request generated during a stopping period, in which fuel injection is stopped to automatically stop engine operation, either starter starting or combustion starting is selected. In the starter starting, the engine is restarted using a starter motor. In the combustion starting, the engine is restarted through fuel injection and ignition without using the starter motor. If the rotational resistance acting on the crankshaft is determined to be of such a magnitude that the combustion starting is impossible, the starter starting is carried out in response to the restarting request generated during the stopping period.

A system for starting an engine of a vehicle has a fuel injector injecting fuel into a closed intake port to form an air fuel mixture. The system also includes an actuator rotating a crankshaft in a first direction to open the intake port by moving a piston within a cylinder coupled to the crankshaft. A combustion chamber defines between the cylinder and the port receiving the air fuel mixture through the intake port. The actuator rotates the crankshaft in a second direction to close the intake port. A spark plug ignites the air fuel mixture to start the engine. The engine also includes many other disclosed features.

An engine control device includes an electronic control unit. The electronic control unit is configured to perform a spark discharge with an ignition plug for each cylinder by cutting off energization after elapse of a predetermined period from start of energization to an ignition coil for each cylinder of the engine, to stop the spark discharge caused by the ignition plug for each cylinder after supply of fuel to the engine is stopped when operation of the engine is stopped, and to control an ignition plug so as to stop the spark discharge caused by the ignition plug from a cylinder after a rotation speed of a crankshaft decreases gradually and the rotation speed of the crankshaft reaches a preset threshold value or less, after the stop of the supply of fuel to the engine.