A gasoline particulate filter (GPF) diagnostic technique utilizes an upstream temperature sensor arranged at an upstream point relative to a GPF brick that the GPF is configured to house and configured to measure an upstream temperature of exhaust gas produced by an engine, a downstream temperature sensor arranged at a downstream point relative to the GPF brick and configured to measure a downstream temperature of the exhaust gas produced by the engine, and a controller configured to detect whether the GPF brick is damaged or missing based on a temperature difference between the upstream and downstream exhaust gas temperatures, a set of temperature thresholds, and a current operational mode of the engine.

A method for operating an internal-combustion engine having an exhaust gas catalyst, a first exhaust gas sensor upstream of the exhaust gas catalyst and a second exhaust gas sensor downstream of the exhaust gas catalyst. A fill level of an exhaust gas component that can be stored in the exhaust gas catalyst is determined using a theoretical catalyst model, into which, as the input value, a signal of the first exhaust gas sensor (a first signal); a signal of the second exhaust gas sensor (a second signal); and a target signal are provided. The target signal corresponds to the signal that would be expected at the determined fill level in the exhaust gas catalyst. The catalyst model is reinitiated when the deviation of the second signal from the target signal exceeds a predetermined threshold value. The fill level is also regulated, and an air-fuel mixture is adjusted.

An engine controller executes a fuel introduction process of introducing, in a state in which the crankshaft of an internal combustion engine is rotating, air-fuel mixture that contains fuel injected by a fuel injection valve into the exhaust passage without burning the air-fuel mixture in the cylinder. When the oxygen concentration of exit gas that has passed through a three-way catalyst decreases during the execution of the fuel introduction process, the engine controller executes a stopping process of stopping the fuel introduction process.

A multi-fuel injector assembly in one embodiment includes a first fuel injector assembly to deliver a first type of fuel and a second fuel delivery system to deliver a second type of fuel. The first fuel injector includes a first nozzle, at least one first needle, and at least one first actuator configured to move the at least one first needle. The at least one first actuator moves the at least one first needle to a first fuel delivery configuration that corresponds to a first fuel mixture composition, and a second fuel delivery configuration that corresponds to a second fuel mixture composition.

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.

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.

Fuel injection control of an engine is executed by setting a required injection amount and an air-fuel ratio correction amount. When setting conditions are met, the air-fuel ratio correction amount is set for a corresponding region to which a current intake air amount or load ratio belongs among a plurality of regions into which the range of the intake air amount or the load ratio is divided such that a region of a larger intake air amount or a higher load ratio becomes wider than a region of a smaller intake air amount or a lower load ratio. When purge conditions are met, a purge control valve is controlled such that purge of supplying an evaporated fuel gas to an intake pipe is executed based on a required purge ratio.

A process for manufacturing an exhaust system, especially for an internal combustion engine of a vehicle, includes providing an exhaust gas-guiding component (26) with a wall (38) made of a metallic material and providing a sensor-mounting connector (22), to be fixed at the wall. The sensor-mounting connector includes a sensor-mounting area (28) to be positioned outside the exhaust gas-guiding component, and a connection area (34), which is to be positioned such that the connection area meshes with the wall. The connection area is pressed against an outer surface (40) of the wall of the exhaust gas-guiding component in a fastening area (39) of the wall, and at the same time rotated about a longitudinal axis (A) of the connector to penetrate into the material forming the wall and a connection in substance is established between the metallic material of the wall and the metallic material of the sensor-mounting connector.

An engine exhaust system includes a catalytic converter, an exhaust conduit connected upstream of the catalytic converter, and an oxygen sensor extending into the exhaust conduit at a first axial position of the exhaust conduit. A valve is located within the exhaust conduit at the first axial position. The valve includes a movable throttle plate having a bypass notch formed on a periphery of the plate. The valve has an open position, and a closed position in which the bypass notch is placed adjacent to the oxygen sensor to guide exhaust over the oxygen sensor.

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.