A powertrain system includes a port injection internal combustion engine. A first start process is a process in which fuel is enclosed in a compression stroke cylinder when the engine is stopped, and based on a stored crank stop position, ignition is performed in a first cycle of the compression stroke cylinder upon engine start. A second start process is a process in which, based on the stored crank stop position, fuel injection is performed for an intake stroke cylinder while the engine is stopped, and based on the stored crank stop position, ignition is performed in the first cycle of the intake stroke cylinder upon engine start. When a catalyst temperature at the time engine start is requested is equal to or higher than a first threshold, a control device starts the internal combustion engine by at least one of the first start process and the second start process.

A method includes determining that at least one diesel emissions fluid (DEF) doser of an exhaust aftertreatment system is likely frozen based on at least one of an ambient air temperature or a DEF source temperature; operating an engine in a cylinder cutout mode in response to the determination that the at least one DEF doser is likely frozen; and, discontinuing the cylinder cutout mode in response to determining that the at least one DEF doser is in a predefined condition.

When an amount of particulate matter (PM) collected by a gasoline particulate filter (GPF) reaches a predetermined amount, a central processing unit (CPU) executes a regeneration process for regenerating the GPF. That is, the CPU stops supply of fuel to any one of cylinders #1 to #4, while increasing an amount of fuel supplied to remaining cylinders. When a temperature of a three-way catalyst becomes equal to or higher than a first temperature, the CPU increases an injection amount to lower a temperature of exhaust gas. When the temperature of the three-way catalyst becomes equal to or higher than the first temperature during the execution of the regeneration process, the CPU does not increase the injection amount.

A controller executes a first suspending process or a second suspending process when a vehicle satisfies a predetermined first condition or a predetermined second condition. The controller executes an integration process that, during execution of the first suspending process or the second suspending process, obtains an integrated value of an intake air amount of the internal combustion engine from when the first suspending process or the second suspending process that is being executed was started. When the integrated value is greater than or equal to a threshold, the controller stops the first suspending process or the second suspending process that is being executed. When the amount of particular matter deposited in a filter is the same, a first threshold, which is the threshold for the first suspending process, is greater than a second threshold, which is the threshold for the second suspending process.

A CPU prompts a user to drive a vehicle to a repair shop by operating a display when an amount of PM deposited in a GPF increases. When a regeneration request for the GPF is input from a shop-side terminal in the repair shop, the CPU performs a regeneration process in a state in which the vehicle stops. The CPU controls a temperature of the GPF such that the temperature at the time of execution of the regeneration process becomes lower when an opening/closing member is in a closed state than when the opening/closing member is in an open state.

A system includes an exhaust aftertreatment system in exhaust gas receiving communication with an engine including a plurality of cylinders where the engine is structured to operate according to low load conditions and where a controller is structured to determine that at least one diesel emissions fluid (DEF) doser is frozen based on at least one of an ambient air temperature and a DEF source temperature. The controller is structured to operate the engine according to a skip-fire mode in response to a DEF flag indicating that the at least one DEF doser is frozen. The skip-fire mode comprises firing a portion of the plurality of cylinders that is less than a total amount of cylinders of the plurality of cylinders. The controller is structured to discontinue the skip-fire mode in response to determining that the at least one DEF doser is likely thawed.

When an amount of particulate matter (PM) collected by a gasoline particulate filter (GPF) reaches a predetermined amount, a central processing unit (CPU) executes a regeneration process for regenerating the GPF. That is, the CPU stops supply of fuel to any one of cylinders #1 to #4, while increasing an amount of fuel supplied to remaining cylinders. When a temperature of a three-way catalyst becomes equal to or higher than a first temperature, the CPU increases an injection amount to lower a temperature of exhaust gas. When the temperature of the three-way catalyst becomes equal to or higher than the first temperature during the execution of the regeneration process, the CPU does not increase the injection amount.

In an internal combustion engine that includes: an EGR channel that connects a portion of an exhaust channel on the upstream side of a downstream-side catalyst and a portion of an intake channel on the downstream side of both of a compressor and a throttle valve; and an EGR valve configured to open and close the EGR channel, a control apparatus is programmed, where an occurrence of a blow-through air that flows from the intake channel to the exhaust channel via the EGR channel is detected, to limit a throttle downstream pressure to reduce the overheating of the downstream-side catalyst.

Methods and systems are provided for controlling an EGR valve and VGT vanes during engine braking. In one example, a method may include during an engine braking event in an engine, coordinating adjustments of both of a cross-sectional area of an inlet of a turbine and an opening of a valve of an exhaust gas recirculation (EGR) system to achieve a desired braking power and to maintain an exhaust system temperature above a threshold temperature during the engine braking event.

Methods and systems for improving operation of an engine at higher speeds and loads are disclosed. In one example, fuel may be injected to an exhaust system of the engine so that temperatures of exhaust system components may be reduced when the engine is operated at higher speeds and loads.