If an engine coolant temperature is equal to or lower than a first low-temperature determination value and a battery temperature is equal to or lower than a second low-temperature determination value when a request to start up an engine is made, the advancement driving of a variable valve operating mechanism is first started. Then, when an advancement amount of the variable valve operating mechanism later becomes equal to or larger than a prescribed startup start determination value, is started.

A variable valve timing assembly is provided for extending a duration of an intake valve opening. The variable valve timing assembly includes an intake rocker mounted on a pedestal and operable by a cam lobe to open and close the intake valve. The intake rocker includes a lever extension, and a holding member in the pedestal is lockable in position by a hydraulic circuit in the pedestal to contact the lever extension of the intake rocker and hold the intake valve in the open position. A reset pin in the pedestal is actuatable by the cam lobe to release the holding member to allow the intake valve to close.

Systems and methods for stopping an engine of a vehicle are described. In one example, the method anticipates when an engine is expected to stop and modifies engine operation so that less fuel is in the engine's intake ports when the engine is stopped so that the fuel may not escape the engine when the engine is restarted.

Closing timing of an intake port is changed without using a variable valve timing mechanism. An electric vehicle includes an engine for electricity generation in which closing timing of an intake port maximizes intake air charging efficiency in a specific revolution speed region, a sensor which outputs a signal related to a revolution speed of the engine, a controller which drives the engine at a revolution speed based on the signal of the sensor, a requested electricity generation amount being satisfied at the revolution speed, and a motor which applies a positive or negative torque to the engine. When the engine is driven in a revolution speed region other than the specific revolution speed region, the controller uses the motor to apply a positive or a negative torque to the engine in an intake stroke to change the closing timing of the intake port to increase intake air charging efficiency.

A method of controlling an engine is provided, which includes, during motoring of the engine, injecting, by an injector, fuel for analysis into a cylinder of the engine at a specific timing after an intake valve of the cylinder is closed. The method includes acquiring, by a controller, a crank angle period from a start timing of the fuel injection to a timing of a pressure inside the cylinder reaching a reference pressure, in response to signals of a crank angle sensor and an in-cylinder pressure sensor. The method includes determining, by the controller, a property of the fuel injected by the injector by comparing the acquired crank angle period with a reference crank angle period, the reference crank angle period being from an injection start timing when a standard fuel is injected into the cylinder to a timing of the pressure inside the cylinder reaching the reference pressure.

An engine controlling method is provided, which includes, during motoring of the engine, outputting, by an in-cylinder pressure sensor, to a controller a signal indicative of a reference pressure corresponding to a pressure change after an intake valve of a cylinder of the engine is closed when not performing fuel injection, and then injecting, by an injector, fuel for analysis into the cylinder at a specific timing after the intake valve is closed. The method includes, by the controller, acquiring a crank angle period from the intake valve close timing, through the fuel injection, to a timing of the in-cylinder pressure reaching the reference pressure based on signals from the in-cylinder pressure sensor and a crank angle sensor, and determining a property of the injected fuel by comparing the acquired crank angle period with that of a standard fuel based on stored information on a property of the standard fuel.

A method of controlling an engine is provided, which includes the steps of, during motoring of the engine, injecting, by an injector, fuel for analysis into a cylinder at a specific timing after an intake valve of the cylinder of the engine is closed, outputting to a controller, by an in-cylinder pressure sensor, a signal corresponding to a pressure inside the cylinder at least at a timing when a specific crank angle period has passed from the fuel injection timing, and determining, by the controller, a property of the fuel injected by the injector, by comparing a pressure value measured by the in-cylinder pressure sensor with a reference pressure value inside the cylinder measured at a timing when the specific crank angle period has passed after a standard fuel is injected into the cylinder at the specific timing.

A control device for an engine is provided, which includes a combustion chamber formed by a cylinder and a piston, an intake air amount adjuster that adjusts an intake air amount supplied to the combustion chamber, a controller switchable of a combustion mode between a fuel-lean first combustion mode and a stoichiometric second combustion mode based on an engine operating state, and an intake air cooler that cools the intake air supplied to the combustion chamber. The controller controls the intake air cooler to start intake air cooling in response to a request for switching the combustion modes, and after the intake air cooling is started, controls the intake air amount adjuster to start the switching of the combustion modes, and then controls the intake air cooler and the intake air amount adjuster so that the switching of the combustion modes ends after the intake air cooling is finished.

Systems and methods provide deceleration fuel cutoff regeneration of a gas particulate filter. A powertrain system includes an exhaust system containing the gas particulate filter, which is configured to collect particulate matter from an exhaust gas stream of the powertrain system. A temperature sensor is configured to monitor a temperature of the gas particulate filter. A loading monitor, such as a sensor and/or a model, is configured to provide a loading input of particulate loading of the gas particulate filter. At least one controller is configured to: determine, by comparing the loading input to stored values, whether the gas particulate filter requires the regeneration; effect a warmup of the gas particulate filter when the determination shows the gas particulate filter requires the regeneration; and initiate the regeneration when a value received from the temperature sensor meets a minimum threshold level.

If an engine coolant temperature is equal to or lower than a first low-temperature determination value and a battery temperature is equal to or lower than a second low-temperature determination value when a request to start up an engine is made, the advancement driving of a variable valve operating mechanism is first started. Then, when an advancement amount of the variable valve operating mechanism later becomes equal to or larger than a prescribed startup start determination value, is started.