Abstract: A vehicle includes an internal combustion engine having a plurality of cylinders, a sensor configured to generate a sensor signal correlated with an air-fuel ratio of first and second cylinders of the plurality of cylinders, and a controller in communication with the sensor and programmed to monitor the air-fuel ratio of the first cylinder in response to an indication that air-fuel ratio measurements of the first cylinder satisfy predetermined criteria for current engine operating conditions while air-fuel ratio measurements of the second cylinder do not satisfy the predetermined criteria for the current engine operating conditions.

Abstract: Methods, apparatus, systems and articles of manufacture to calibrate a weight estimation are disclosed herein. An example apparatus comprises memory including stored instructions, and a processor to execute the instructions to determine, via a first sensor, a first load estimation of a vehicle corresponding to when the vehicle under a load condition, determine, via a second sensor, a second load estimation corresponding to when the vehicle is moving and under the load condition, and calibrate, based on a difference between the second load estimation and the first load estimation, an error of the first load estimation.

Abstract: Methods, apparatus, systems and articles of manufacture to calibrate a weight estimation are disclosed herein. An example apparatus comprises memory including stored instructions, and a processor to execute the instructions to determine, via a first sensor, a first load estimation of a vehicle corresponding to when the vehicle under a load condition, determine, via a second sensor, a second load estimation corresponding to when the vehicle is moving and under the load condition, and calibrate, based on a difference between the second load estimation and the first load estimation, an error of the first load estimation.

Abstract: 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.

Abstract: Methods and systems are provided for balancing a plurality of fuel injectors. In one example, a method includes adjusting port-fuel injecting parameters in response to a learned direct injector fueling error.

Abstract: Methods and systems are provided for detection of cylinder misfire in an engine. In one example, a system may comprise a first cylinder and second cylinder of the engine having exhaust flows combined together in an exhaust system before being combined with other cylinders of the engine. The first cylinder and second cylinder may share an exhaust gas sensor mounted in the exhaust in a position to sense exhaust from the first cylinder and second cylinder, and being positioned before exhaust from other cylinders is combined with sensed exhaust from the first cylinder and second cylinder. The system may further include a control system with instructions stored therein to indicate detected misfire in one or more of the first and second sensors based on an output from the exhaust gas sensor.

Abstract: Methods and systems are provided for detection of cylinder misfire in an engine. In one example, a system may comprise a first cylinder and second cylinder of the engine having exhaust flows combined together in an exhaust system before being combined with other cylinders of the engine. The first cylinder and second cylinder may share an exhaust gas sensor mounted in the exhaust in a position to sense exhaust from the first cylinder and second cylinder, and being positioned before exhaust from other cylinders is combined with sensed exhaust from the first cylinder and second cylinder. The system may further include a control system with instructions stored therein to indicate detected misfire in one or more of the first and second sensors based on an output from the exhaust gas sensor.

Abstract: 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.

Abstract: Methods and systems are provided for a fuel injector diagnostic. In one example, a method may include modifying an injection pattern to determine a relative fuel mass error of an injector. A fuel injector correction may be determined based the relative fuel mass error.

Abstract: Methods and systems are provided for a fuel injector diagnostic. In one example, a method may include modifying an injection pattern to determine a relative fuel mass error of an injector. A fuel injector correction may be determined based the relative fuel mass error.

Abstract: Methods and systems for adjusting fuel injector operation according to changes in fuel pressure during inter-injection periods are described. The inter-injection period may be before and after fuel is injected to an engine. The methods and systems described herein may be suitable for direct and port fuel injectors.

Abstract: Systems and methods for improving operation of a vehicle are presented. In one example, a controller may respond to a temperature of a catalyst to permit or temporarily inhibit a vehicle from moving. Engine load and engine emissions may be reduced by limiting vehicle motion until a catalyst temperature exceeds a threshold temperature.

Abstract: Methods and systems are provided for providing secondary air to an exhaust system during catalyst warm-up. In one example, a method may include, during a cold start condition, operating an engine with a first number of cylinders unfired and a remaining number of cylinders fired during an engine cycle, opening an intake valve of an unfired cylinder of the first number of cylinders during an expansion stroke of the unfired cylinder, and opening an exhaust valve of the unfired cylinder during a compression stroke of the unfired cylinder. In this way, the unfired cylinders may provide the secondary air to the exhaust system during a stroke that increases mixing of the secondary air with burned exhaust gas from fired cylinders, thus increasing exotherm production in the exhaust system to increase a temperature of the catalyst.

Abstract: Methods and systems for operating an engine that includes adjustable poppet valve timing and an exhaust gas recirculation valve are described. In one example, the exhaust gas recirculation valve is opened and the timing of the poppet valves is retarded so that an amount of fresh air that is pumped by the engine to an after treatment device may be reduced.

Abstract: Systems and methods for preparing an engine for a cold start are described. In one example, the air is injected into one or more pre-chambers of engine cylinders in response to an engine start request so that one or more cylinders may be heated before the engine is started. The engine may or may not be rotated while air is being injected to pre-chambers of engine cylinders.

Abstract: Methods and systems to determine a presence or absence of engine misfire or spark plug fouling are presented. In one example, rates of change in engine speed are arranged in engine data blocks and root mean square values for the rates of change in engine speed are determined. The presence or absence of engine misfire or spark plug fouling may be based at least in part on the root mean square values.

Abstract: Methods and systems are provided for controlling a vehicle including a manual transmission to prevent cold-start drive-away. In one example, a method for a vehicle with a driver clutch pedal may include preventing one of a clutch coupled between an input of a transmission and an engine output from closing and a driver-operated gearshift lever for adjusting a gear of the transmission from coming out of neutral in response to a catalyst light-off condition.

Abstract: Methods and systems are provided for a diagnostic routine of a variable displacement engine (VDE) of a vehicle to detect non-deactivated valves of deactivated cylinders due to a degraded valve deactivation mechanism. In one example, a method comprises, during operation of the VDE with one or more cylinders of the VDE deactivated, calculating a variation in a fast-sampled signal outputted by one or more exhaust gas oxygen (EGO) sensors of the VDE over a plurality of engine cycles; determining that the variation is greater than the threshold variation; and in response, indicating that valves of the one or more cylinders are not deactivated. A second method comprises estimating a throttle air flow rate and an engine air flow rate of the VDE; and indicating non-deactivated valves of one or more deactivated cylinders if the throttle air flow rate exceeds the engine air flow rate by a threshold.

Abstract: Methods, apparatus, systems and articles of manufacture to calibrate a weight estimation are disclosed herein. An example apparatus comprises memory including stored instructions, and a processor to execute the instructions to determine, via a first sensor, a first load estimation of a vehicle corresponding to when the vehicle under a load condition, determine, via a second sensor, a second load estimation corresponding to when the vehicle is moving and under the load condition, and calibrate, based on a difference between the second load estimation and the first load estimation, an error of the first load estimation.

Abstract: Methods and systems are provided for balancing a plurality of fuel injectors. In one example, a method includes adjusting port-fuel injecting parameters in response to a learned direct injector fueling error.