An engine system provided to a vehicle having an accelerator pedal is provided. When an engine operation range is determined to shift to a first range (where an electromagnetic clutch is disengaged) from a second range (where the clutch is engaged) after an opening of the accelerator pedal increases at a rate below a given reference rate, the clutch is switched from ON to OFF after a given basic stand-by period passes from the shift. When the engine operation range is determined to shift from the second range to the first range after the accelerator pedal opening increases at the given reference rate or above, the clutch is switched from ON to OFF after a given acceleration stand-by period (longer than the basic stand-by period by a given added period) passes from the shift.

The present invention describes a fuel-management system for minimizing particulate emissions in turbocharged direct injection gasoline engines. The system optimizes the use of port fuel injection (PFI) in combination with direct injection (DI), particularly in cold start and other transient conditions. In the present invention, the use of these control systems together with other control systems for increasing the effectiveness of port fuel injector use and for reducing particulate emissions from turbocharged direct injection engines is described. Particular attention is given to reducing particulate emissions that occur during cold start and transient conditions since a substantial fraction of the particulate emissions during a drive cycle occur at these times. Further optimization of the fuel management system for these conditions is important for reducing drive cycle emissions.

This fuel includes: a first switching element disposed between a booster circuit boosting a battery power and one end of a solenoid; a second switching element disposed between a battery and one end of the solenoid; a third switching element disposed between the other end of the solenoid and a ground; a fourth switching element disposed between one end of the solenoid and a ground; and a control unit configured to control open/closed states of the first switching element, the second switching element, the third switching element, and the fourth switching element. The control unit is configured to open the fourth switching element during a valve closing detection period of detecting closing of a fuel injection valve and to detect the closing of the fuel injection valve on the basis of a change in voltage of the other end of the solenoid.

This fuel includes: a first switching element disposed between a booster circuit boosting a battery power and one end of a solenoid; a second switching element disposed between a battery and one end of the solenoid; a third switching element disposed between the other end of the solenoid and a ground; a fourth switching element disposed between one end of the solenoid and a ground; and a control unit configured to control open/closed states of the first switching element, the second switching element, the third switching element, and the fourth switching element. The control unit is configured to open the fourth switching element during a valve closing detection period of detecting closing of a fuel injection valve and to detect the closing of the fuel injection valve on the basis of a change in voltage of the other end of the solenoid.

A conventional gasoline engine is retrofitted and calibrated to operate as a bi-fuel engine using Hydrogen as the second fuel. When operated with Hydrogen, which typically leads to a reduction of engine output power, the engine is preferably operated in a charged mode and in a lean mode with the engine throttle kept in a wide-open position during charged and lean mode operation resulting in a more efficient engine with a reduction of engine output power loss.

A system and method for a variable displacement internal combustion engine using different types of pneumatic cylinder springs on skipped working cycles to control engine and aftertreatment system temperatures are described. The system and method may be used to rapidly heat up the aftertreatment system(s) and/or an engine block of the engine following a cold start by using one or more different types of pneumatic cylinder springs during skipped firing opportunities. By rapidly heating the aftertreatment system(s) and/or engine block, noxious emissions such as hydrocarbons, carbon monoxide, NO.sub.x and/or particulates, following cold starts are significantly reduced.

Systems and methods for estimating a temperature of an after treatment device in an exhaust system of an engine are described. In one example, the temperature is estimated during condition when an engine exits a fuel cut-out mode and excess fuel is delivered to the after treatment device for the purpose of increasing after treatment device efficiency.

A method of controlling an engine is provided, which includes setting, by a controller, a target torque of the engine in a specific cycle in the future by a given delay time from the present time based on a present accelerator opening. The method includes selecting beforehand, by the controller, combustion in the specific cycle according to the target torque, from flame propagation combustion and compressed self-ignition combustion. The method includes outputting, by the controller, a control signal to a property adjusting device before the specific cycle so that a property inside the cylinder in the specific cycle becomes a property corresponding to the selected combustion. The method includes estimating, by the controller, the property at a timing when an intake valve is closed in the specific cycle. The method includes outputting, by the controller, a control signal corresponding to the estimated property to a spark plug or an injector.

An engine system is provided, which includes a vehicle-mounted engine having an injector, a spark plug, an intake valve operating mechanism, and an exhaust valve operating mechanism, an accelerator opening sensor, and a controller. The engine is configured to execute flame propagation combustion and compressed self-ignition combustion. The controller performs a combustion control so that a target torque set based on an accelerator opening is realized in a specific cycle in the future from a present time by a given delay time. The controller sets beforehand the combustion mode based on a target load, estimates an in-cylinder property when the intake valve is closed in the present cycle, sets a target in-cylinder property so that the set combustion mode is realized in the specific cycle, and sets a target operating amount of each of the intake and exhaust valve operating mechanisms based on the set target in-cylinder property.

Identifying position of a first rotating shaft may comprise a first position detection system and a second position detection system. A controller may be coupled to a first sensor and a second sensor and may identify the position of the first shaft using the identified shaft position from either the first detection system or the second detection system, whichever is identified faster. The first shaft may have a first wheel disposed thereon with targets and one or more gaps disposed about the first wheel. A second shaft may have a second wheel disposed thereon with targets and one or more gaps disposed thereon. The second wheel is in a fixed relationship relative to the first wheel. The first detection system may use data simultaneously from the first sensor and the second sensor to eliminate targets to determine position. The second detection system uses data only from the first sensor.