Methods and systems are provided for operating a cylinder of an engine including a pre-chamber ignition system during a cold start condition. In one example, a method may include performing a post-injection in the cylinder, and then performing a pre-chamber combustion during an exhaust stroke of the cylinder. In this way, a temperature of a catalyst of the engine may be increased, which may decrease vehicle emissions during the cold start condition.

Methods and systems are provided for operating a cylinder of an engine including a pre-chamber ignition system during a cold start condition. In one example, a method may include performing a post-injection in the cylinder, and then performing a pre-chamber combustion during an exhaust stroke of the cylinder. In this way, a temperature of a catalyst of the engine may be increased, which may decrease vehicle emissions during the cold start condition.

A motor response control method in a variable charge motion system in which a VCM motor is differentially controlled by a PWM duty regardless of back pressure of intake air in an intake manifold when a current engine rotation speed in revolutions per minute is less than a specific engine rotation speed in revolutions per minute in a VCM position learning state by a controller whereas the VCM motor is differentially controlled by the PWM duty based on the back pressure of intake air in the intake manifold when the current engine rotation speed in revolutions per minute is greater than the specific engine rotation speed in revolutions per minute.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate drift, obstruction and bias estimates.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate drift, obstruction and bias estimates.

An engine with a vertically oriented parallel valve and stem arrangement accommodating tumble flow to support spark-ignited fuel usage. The engine may be provided in a configuration generally suited for swirl flow, compression combustion fuel usage. However, the introduction of a unique, replaceable valve head assembly may be utilized to induce tumble flow within a combustion chamber of the engine. Thus, spark-ignited fuel may be utilized without requiring vast overhaul of the engine to accommodate such fuels. Notably, with the addition of such an assembly, diesel fuel may be replaced with natural gas on large scale equipment without the requirement of impractically burdensome or expensive measures.

An engine with a vertically oriented parallel valve and stem arrangement accommodating tumble flow to support spark-ignited fuel usage. The engine may be provided in a configuration generally suited for swirl flow, compression combustion fuel usage. However, the introduction of a unique, replaceable valve head assembly may be utilized to induce tumble flow within a combustion chamber of the engine. Thus, spark-ignited fuel may be utilized without requiring vast overhaul of the engine to accommodate such fuels. Notably, with the addition of such an assembly, diesel fuel may be replaced with natural gas on large scale equipment without the requirement of impractically burdensome or expensive measures.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate drift, obstruction and bias estimates.

Methods and systems for calculating a plurality of aging factors in a system operating an engine. The calculated aging factors may include one or more of fuel injector drift, exhaust gas recirculation valve obstruction, and mass air flow sensor bias. Mass flow throughout the system, and pressures and temperatures within the system, are observed in an approach that relies on mass preservation concepts to estimate drift, obstruction and bias estimates.

Apparatuses, methods, and systems for igniting fuel for an internal combustion engine, an ignition system include a first ignition device associated with a pre-combustion chamber of a cylinder and a second ignition device associated with a main combustion chamber of the cylinder. An engine control unit is operably connected to both the engine and the ignition system to ignite fuel for the cylinder with the first ignition device independently of igniting fuel with the second ignition device. The engine control unit determines an occurrence of a combustion condition and in response thereto (i) ignites fuel for combustion with both the first and the second ignition devices or (ii) ignites fuel for combustion only with the second ignition device. The engine control unit determines a second combustion condition and in response thereto ignites fuel only with the first ignition device.