Methods and systems are provided for compression heating of air. In one example, a method may include, during an engine start and prior to a first combustion event, deactivating cylinder exhaust valves while spinning the engine electrically and unfueled until a threshold intake air temperature is reached, and alternately activating and deactivating the exhaust valves of one or more cylinders to maintain the intake air temperature above the threshold temperature after the first combustion event. In this way, a temperature of an air charge may be increased, resulting in increased fuel economy and decreased vehicle emissions.

A disclosed method of automatically stopping and restarting a vehicle engine determines if one or more stop/start enablement condition has been met. If the stop/start enablement condition or conditions have been met, the method initiates an engine shutdown. If a restart request is made before the engine reaches a predetermined threshold speed, then a first restart sequence is initiated. If a restart request is made when the engine speed is less than the predetermined threshold speed but still greater than 0, then a second restart sequence is initiated.

A controller for an internal combustion engine includes: a failure determination section which determines a failure state in a case where a relative rotation phase of an intake side valve opening and closing timing control mechanism does not change when controlling the mechanism after starting the driving of a starter motor and trying to change the relative rotation phase of the mechanism in a start control for starting an internal combustion engine. When the section determines a failure, the controller performs at least one of an intake air amount increase control in which an opening degree of a throttle valve is increased, an ignition timing advance angle control in which injection of fuel is performed at a timing earlier than a set timing and ignition is performed, and a multi-injection control in which the fuel is injected immediately before the ignition in addition to the fuel injection in an intake stroke.

Methods and systems are provided for relieving pressure from a compression locked engine. The engine may be compression locked during an engine start attempt due to operator application of a manual transmission clutch at or around the time of a first combustion event of the engine start. A direct injector of the compression locked cylinder is commanded open to relieve the pressure into the fuel rail.

An internal combustion engine includes: an intake control valve provided on an upstream side of a fuel injection device provided in an intake flow path and configured to adjust an opening degree thereof while maintaining an intake state through the intake flow path; and a controller configured to perform control to adjust the opening degree of the intake control valve, in which the controller is configured to set the intake control valve to a closing direction side such that a pressure between the intake control valve and an intake valve of a combustion chamber increases during a pre-ignition motor drive period until a fuel is supplied to the combustion chamber and first ignited.

A miller cycle engine according to the present disclosure includes: a variable valve operating device configured to continuously change the closing timing of an intake valve; a throttle valve arranged in an intake air passage; and a control device configured to execute an early closing miller cycle operation mode to control the variable valve operating device such that the intake valve closes at an intake bottom dead center or earlier. The control device is configured to: execute a late closing mode (e.g., decompression mode) to retard the closing timing relative to the intake bottom dead center at the time of engine start-up; and execute, where the pressure in the intake air passage has decreased to a first threshold value or lower first after the engine start-up, a mode switching processing to switch from the late closing mode to the early closing miller cycle operation mode.

The invention relates to a method for starting an internal combustion engine for a motor vehicle, said internal combustion engine having at least two cylinders, a valve drive with at least one inlet valve and at least one outlet valve for each of the cylinders, wherein at least the closing times of the inlet valves can be variably adjusted, and a direct injection system, in particular a gasoline direct injection system, the starting process being initiated by a direct injection and ignition in one of the cylinders. During a starting process, the closing time of at least one inlet valve differs from at least one of the other cylinders dependent on at least one current state value.

An engine start control device is provided with: a starter relay that is provided between a battery and a starter motor; a start abnormality determining means that determines the occurrence of start abnormality of an engine; and a start control means, which turns on the starter relay, and starts supplying power from the battery to the starter motor in the cases where a start instruction signal is inputted from a start switch, and which turns off the starter relay in the cases where the start abnormality determining means determined the occurrence of start abnormality of the engine.

A valve timing controller includes: a driving side rotation member that rotates synchronously with a crankshaft of an internal combustion engine; a driven side rotation member that integrally rotates with a cam shaft of the internal combustion engine; a phase regulating mechanism with which a relative rotation phase of the driving and driven side rotation members around a rotation axis is set by a driving force of an electric motor; a phase sensing portion that acquires the relative rotation phase; and a phase controlling section that controls the electric motor to set the relative rotation phase based on an acquisition result by the phase sensing portion. The phase sensing portion includes a cam angle sensor, a reference determination sensor, and a pattern storage unit. The valve timing controller further includes a phase acquisition portion.

A method of implementing control logic of a compression-ignition engine is provided. A controller outputs a signal to a injector and a variable valve operating mechanism so that a gas-fuel ratio (G/F) becomes leaner than a stoichiometric air fuel ratio, and an air-fuel ratio (A/F) becomes equal to or richer than the stoichiometric air fuel ratio, and to an ignition plug so that unburnt mixture gas combusts by self-ignition after the ignition plug ignites mixture gas inside a combustion chamber. The method includes steps of determining a geometric compression ratio and determining the control logic defining an intake valve close timing IVC. IVC (deg.aBDC) is determined so that the following expression is satisfied: if the geometric compression ratio is 10<17,

0.4234.sub..sup.222.926.sub.+207.84+CIVC0.4234.sub..sup.2+22.926.sub.167.84+C

where C is a correction term according to an engine speed NE (rpm),

C=3.310.sup.10NE.sup.31.010.sup.6NE.sup.2+7.010.sup.4NE.