A controller for an internal combustion engine includes processing circuitry that executes a richening process until an exhaust sensor detects exhaust gas having a rich air-fuel ratio. The processing circuitry executes an air supplying process to supply a catalytic converter with air until the exhaust sensor detects that the exhaust gas has a lean air-fuel ratio. The processing circuitry cumulates the amount of air supplied to the catalytic converter until the exhaust sensor detects that the exhaust gas has a lean air-fuel ratio in the air supplying process. The air supplying process includes stopping fuel supplied to the one or more of the cylinders and performing combustion at an air-fuel ratio that is less than or equal to the stoichiometric air-fuel ratio in the remaining one or more of the cylinders.

Methods and systems are provided for an aftertreatment system. In one example, a system comprising a spark-ignited engine comprising a selective catalytic reduction device (SCR) arranged in an exhaust passage downstream of a catalyst, and an injector positioned to inject a reductant directly into the exhaust passage downstream of the catalyst subsequent an engine shut-off event.

Provided are an exhaust purification device and an exhaust purification method which can achieve improved fuel efficiency. The exhaust purification device (100) is equipped with: a DOC (5) for occluding hydrocarbons in an exhaust gas; a DPF (6) that is provided downstream from the DOC (5) and is for trapping particulate matter in the exhaust gas; and an ECU (10) for determining, in accordance with the amount of occluded hydrocarbons in the DOC (5), a start time for a regeneration process for removing particulate matter accumulated in the DPF (6).

A fuel injector assembly in one embodiment includes a nozzle, at least one needle, and at least one actuator. The nozzle includes at least one cavity in fluid communication with nozzle openings. The at least one needle is movably disposed within the at least one cavity, and prevents flow through the nozzle openings in a closed position. The at least one actuator is configured to move the at least one needle within the cavity. The at least one actuator is configured to move the at least one needle to at least a first fuel delivery configuration and a second fuel delivery configuration. A first amount of fuel is delivered through the nozzle openings with the at least one needle in the first fuel delivery configuration, and a second amount of fuel is delivered through the nozzle openings with the at least one needle in the second fuel delivery configuration.

A method for ascertaining emissions of a motor vehicle driven with the aid of an internal combustion engine in a practical driving operation. A machine learning system is trained to generate time curves of the operating variables with the aid of measured time curves of operating variables of the motor vehicle and/or of the internal combustion engine, and to then ascertain the emissions as a function of these generated time curves.

A control system of an internal combustion engine comprises an air-fuel ratio sensor 40, 41 detecting an air-fuel ratio of exhaust gas, a current detecting device 61 detecting an output current of the air-fuel ratio sensor, a voltage applying device 60 applying voltage to the air-fuel ratio sensor, and a voltage control part 81 configured to control voltage applied to the air-fuel ratio sensor through the voltage applying device. The voltage control part is configured to set the applied voltage to a reference voltage determined so that the output current becomes zero when an air-fuel ratio of inflowing exhaust gas flowing into the air-fuel ratio sensor is a stoichiometric air-fuel ratio, and correct the reference voltage so that the output current detected by the current detecting device becomes zero when it is judged that the air-fuel ratio of the inflowing exhaust gas is the stoichiometric air-fuel ratio.

A method of controlling an air-fuel ratio in a pre-ignition (PI) situation, may include: monitoring, by a PI detector, whether PI occurs in a cylinder of a plurality of cylinders of an engine; and when the PI occurs in the cylinder of the plurality cylinders, controlling, by a controller, an air-fuel ratio of the cylinder in which the PI occurs to be smaller than a theoretical air-fuel ratio, and controlling an air-fuel ratio of a remaining cylinder of the plurality of cylinders in which PI does not occur to be larger than the theoretical air-fuel ratio.

An engine system for a vehicle includes an internal combustion engine having an exhaust gas outlet, an exhaust system having a three-way catalyst and a switch-type post oxygen sensor, and an engine control module that controls the engine system. The engine control module includes a first control logic for estimating a three-way catalyst oxygen storage capacity based on a plurality of measured inputs, a second control logic for estimating aging effects of the switch-type post oxygen sensor, and a third control logic that calculates a filtered estimated three-way catalyst oxygen storage capacity for the three-way catalyst.

A method for adjusting an air-fuel ratio of a turbocharged engine that operates without blow though and with blow through is disclosed. In one example, the method provides a way to provide a feed forward fuel adjustment in the presence of engine blow though so that a closed loop controller does not have to exceed its range of control authority.

Various embodiments include a method for diagnosing a crankcase ventilation line of a crankcase ventilation device for an internal combustion engine having a crankcase, an intake tract, and a compressor arranged in the intake tract for compressing the intake air comprising: diverting fresh air from the intake tract via a fresh air supply line; either enabling or inhibiting a flow of fresh air into a free volume of the crankcase depending on a switch position of a shut-off valve in the fresh air supply line; detecting a nitrogen oxide concentration in the crankcase during the process of crankcase ventilation, close to the point of introduction into the intake tract upstream of the compressor using a nitrogen oxide sensor; and evaluating the tightness of the crankcase ventilation line based at least in part on the detected nitrogen oxide concentration.