A control value calculation part includes an in-cylinder state estimation part that estimates a state to which the cylinder belongs between a plurality of PM-PN generation states. The plurality of PM-PN generation states are states in which a particulate matter is easily generated as compared with the other state, and are different from each other in a cause to generate the particulate matter. Further, in a case where it is determined that an operation state of an engine is a PM-PN exhaust state, the control value calculation part calculates a control value of an actuator in such a way to eliminate the PM-PN generation state according to the PM-PN generation state to which the state in the cylinder belongs.

A control device for a compression ignition engine is provided, which causes an injector to perform a pre-injection and a main injection, sets fuel injection timings of these injections so that an interval between a first peak of a heat release rate resulting from the combustion of fuel injected by the pre-injection and a second peak of the heat release rate resulting from the combustion of fuel injected by the main injection becomes an interval to make pressure waves caused by these combustions cancel each other out, and when an increase of an intake air temperature is detected, controls the injector to reduce the injection amount of the pre-injection and retard the injection timing of the pre-injection compared with a case where the increase of the intake air temperature is not detected under a condition that engine load and speed are the same.

An injection control device controls a solenoid in a fuel injection valve. The injection control device includes a transistor on an upstream side of a first power supply path to the solenoid and a transistor on an upstream side of a second power supply path to the solenoid. The injection control device has another transistor with a body diode arranged in parallel at a position on the first power supply path between the first transistor and an upstream terminal of the solenoid. The injection control device also includes a transistor on the downstream side of the first and second power supply paths. A drive controller in the injection control device drives the solenoid to an open position by switching ON the transistor on the downstream side and the transistor on the upstream side of the first power supply path or the transistor on the upstream side of the second power supply path.

A direct fuel injection engine including an ignition plug and a fuel injection valve arranged to be capable of injecting a fuel directly in a cylinder is controlled. The engine has a predetermined operation region in which an excess air ratio of an air-fuel mixture is set in a vicinity of 2. In a first region on a low load side of the predetermined operation region, a homogenous air-fuel mixture having the excess air ratio at a first predetermined value in the vicinity of 2 is formed upon combustion, and in a second region on a load side higher than the first region, a stratified air-fuel mixture having the excess air ratio at a second predetermined value in the vicinity of 2 is formed upon combustion.

A direct fuel injection engine including an ignition plug and a fuel injection valve arranged to be capable of injecting a fuel directly in a cylinder is controlled. The engine has a predetermined operation region in which an excess air ratio of an air-fuel mixture is set in a vicinity of 2. In a first region on a low load side of the predetermined operation region, a homogenous air-fuel mixture having the excess air ratio at a first predetermined value in the vicinity of 2 is formed upon combustion, and in a second region on a load side higher than the first region, a stratified air-fuel mixture having the excess air ratio at a second predetermined value in the vicinity of 2 is formed upon combustion.

A control device for a compression ignition engine is provided, which causes an injector to perform a pre-injection and a main injection, sets fuel injection timings of these injections so that an interval between a first peak of a heat release rate resulting from the combustion of fuel injected by the pre-injection and a second peak of the heat release rate resulting from the combustion of fuel injected by the main injection becomes an interval to make pressure waves caused by these combustions cancel each other out, and when an increase of an intake air temperature is detected, controls the injector to reduce the injection amount of the pre-injection and retard the injection timing of the pre-injection compared with a case where the increase of the intake air temperature is not detected under a condition that engine load and speed are the same.

A fuel system for an internal combustion engine includes a fuel control system having a fueling control unit structured to determine a test point on a tip wear-sensitive region of a fuel injector delivery curve, and store measurements of pressure drops in a pressurized fuel reservoir caused by injections of fuel at the test point. The fueling control unit is further structured to produce an injector health signal based on the stored measurements of pressure drop. Related methodology and control logic for calculation of wear parameters for injection signal duration electronic trimming and prognostic health determinations are also disclosed.

A method and system for determining remaining useful life of an in-use injector of a reciprocating engine is disclosed. The method includes determining nozzle wear relationship data for different duty cycles of the in-use injector, and using the nozzle wear relationship data together with operating parameters for the reciprocating engine, and emission relationship data to determine actual emission levels for the in-use injector based on the wear relationship data and the emission relationship data. The method and system further include determining remaining useful life of the in-use injector based on actual emission levels and the nozzle wear relationship data; and controlling an operation of the reciprocating engine based on the actual emission levels.

An injection control device controls a solenoid in a fuel injection valve. The injection control device includes a transistor on an upstream side of a first power supply path to the solenoid and a transistor on an upstream side of a second power supply path to the solenoid. The injection control device has another transistor with a body diode arranged in parallel at a position on the first power supply path between the first transistor and an upstream terminal of the solenoid. The injection control device also includes a transistor on the downstream side of the first and second power supply paths. A drive controller in the injection control device drives the solenoid to an open position by switching ON the transistor on the downstream side and the transistor on the upstream side of the first power supply path or the transistor on the upstream side of the second power supply path.

A fuel injection control device for an internal combustion engine includes an electronic control unit configured to execute division processing for learning for dividing a requested injection amount into an injection amount of partial lift injection of an in-cylinder injection valve and a port injection amount of injection of a port injection valve, detect, on the basis of at least one of a terminal electric potential of a coil and a current flowing through the coil, an inflection point of a change in induced electromotive force of the coil in time attributable to a decline in a relative speed of a mover with respect to the coil, and correct the energization processing at a time when the partial lift injection is executed based on a timing of the detection of the inflection point.