An internal combustion engine includes a fuel injection nozzle provided with a nozzle hole for injecting fuel, the nozzle hole exposed from a cylinder head of the internal combustion engine to a combustion chamber, and a hollow duct, an inlet and an outlet of which are exposed to the combustion chamber. The duct is provided in a manner allowing fuel spray injected from the nozzle hole of the fuel injection nozzle to pass through from the inlet to the outlet. The fuel injection nozzle and the duct are configured such that a part of fuel spray that is injected in pilot injection that is performed before main injection directly adheres to an inner wall surface of the duct.

An estimation device is applicable to a combustion system including an internal combustion engine and includes a mixing acquisition unit, a main region estimation unit, and an after region estimation unit. The mixing acquisition unit acquires a mixing ratio of various components contained in the fuel used for combustion in the internal combustion engine. The main region estimation unit estimates a combustion region of the fuel as a main combustion region for a main combustion produced by injecting the fuel into a combustion chamber of the internal combustion engine by main injection, based on the mixing ratio acquired by the mixing acquisition unit. The after region estimation unit estimates an injection region of the fuel as the after combustion region based on the mixing ratio, for an after combustion produced by injecting the fuel into the combustion chamber by an after injection, after the main injection in one combustion cycle.

Methods and systems are provided for increasing an efficiency of a purging operation of a fuel vapor storage canister of a vehicle, the fuel vapor storage canister configured to capture and store fuel vapors stemming from a fuel tank of the vehicle. As one example, a method comprises reactivating one or more cylinders of an engine during a purging operation, in response to an indication that the purging of stored fuel vapors from the fuel vapor storage canister is compromised as a result of fuel vaporization stemming from the fuel tank. In this way, the canister may be effectively cleaned even under high fuel vaporization circumstances, which may improve fuel economy and may reduce release of undesired evaporative emissions to atmosphere.

Provided is a fuel injection control device that makes it possible to precisely estimate an amount of fuel remaining in an air intake passage at a start-up of an engine, and to precisely set an fuel injection amount during start-up operation. In the fuel injection control device of the present invention, in a process in which the engine is transferred from operation state to a stop state, engine stop information is acquired and stored in a nonvolatile memory, the engine stop information including, at least an information indicating whether the current engine stop is an intended stop accompanied by fuel cutting. During the start-up of the engine, judgement is made as to whether the last engine stop was the intended stop or not, based upon the engine stop information and a fuel injection amount during start-up operation is determined with reference to the result of the judgement.

In a predetermined operating region, a fuel injection valve executes a second injection to inject fuel into a cylinder in a compression stroke, and a first injection to inject fuel into the cylinder 2 in the compression stroke or an intake stroke before the second injection. When a purge is executed, the total quantity of fuel to be injected by the fuel injection valve into the cylinder is reduced more than when the purge is not executed, and a fuel reduction quantity of the second injection is made smaller than a fuel reduction quantity of the first injection.

Systems and methods are provided for cooling an overheated engine using a combination of variable displacement engine (VDE) technology and direct injection technology. In one example, a method may include deactivating a subset of engine cylinders based on an engine temperature and directly injecting liquid fuel into the deactivated cylinders. In this way, an increased thermal conductivity of the liquid fuel compared to air decreases the engine temperature at a faster rate than when air-based engine cooling methods are used, thereby preventing overheating-related engine degradation.

A fuel injection control apparatus switches between MPI and DI+MPI modes. The apparatus includes a unit calculating a DI direct combustion rate that is the rate of that portion of the amount of DI injection corresponding to a fuel combusted instead of adhering to inside of the cylinder, and a unit calculating a cylinder vaporization rate that is the rate of the amount of that portion of the fuel adhering to the inside of the cylinder which vaporizes. The former unit controls fuel injection based at least on the DI direct combustion rate and the cylinder vaporization rate. When the mode is switched between the MPI mode and the DI+MPI mode, the former unit corrects the DI direct combustion rate or the cylinder vaporization rate to set the amount of fuel injection to a value different from that set when the fuel injection modes are maintained.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

Systems and methods for determining fuel delay in a fuel injected engine with cylinders that may be deactivated are presented. In one example, the fuel injection delay is determined via a cylinder firing schedule array when the cylinder firing schedule array is available. The fuel injection delay is determined via weighted average of a fuel injection delay of a present engine cycle and a fuel injection delay of a past engine cycle when the cylinder firing schedule array is not available.

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.