Abstract: Embodiments for diagnosing a humidity sensor are provided. One example method comprises adjusting an engine operating parameter based on humidity of a first gas flow measured by a humidity sensor, and indicating degradation of the humidity sensor if a humidity of a second gas flow measured by the humidity sensor is different than an expected humidity. In this way, degradation of the humidity sensor may be indicated if the humidity of the second gas flow measured by the humidity sensor is different than expected.

Abstract: Methods and systems are provided for learning fuel injector error for cylinder groups during a deceleration fuel shut-off (DFSO), where all cylinders of an engine are deactivated, sequentially firing each cylinder of a cylinder group, each cylinder fueled via consecutive first and second fuel pulses of differing fuel pulse width from an injector. Based on a lambda deviation between the first and second pulses, a fuel error for the injector and an air-fuel ratio imbalance for each cylinder is learned. Alternatively or additionally, a difference in crankshaft acceleration between the first and second pulses relative to the expected deviation may be used to learn torque error, and adjust fuel injector error and air-ratio imbalance for each cylinder.

Abstract: Methods and systems are provided for converting an asymmetric sensor response of an exhaust gas sensor to a symmetric response. In one example, a method includes adjusting fuel injection responsive to a modified exhaust oxygen feedback signal from an exhaust gas sensor, where the modified exhaust oxygen feedback signal is modified by transforming an asymmetric response of the exhaust gas sensor to a symmetric response. Further, the method may include adapting parameters of an anticipatory controller of the exhaust gas sensor based on the modified symmetric response.

Abstract: Methods and systems include determining a cylinder air-fuel ratio imbalance in a multi-cylinder engine. In one example, the method may include sequentially firing an engine cylinder to provide an expected air-fuel deviation and learning cylinder air-fuel ratio imbalance based on an error between an actual air-fuel ratio deviation from a maximum lean air-fuel ratio relative to an expected air-fuel deviation during a deceleration fuel shut-off event.

Abstract: Methods and systems are provided for learning fuel injector error for cylinder groups during a deceleration fuel shut-off (DFSO), where all cylinders of an engine are deactivated, sequentially firing each cylinder of a cylinder group, each cylinder fueled via consecutive first and second fuel pulses of differing fuel pulse width from an injector. Based on a lambda deviation between the first and second pulses, a fuel error for the injector and an air-fuel ratio imbalance for each cylinder is learned. Alternatively or additionally, a difference in crankshaft acceleration between the first and second pulses relative to the expected deviation may be used to learn torque error, and adjust fuel injector error and air-ratio imbalance for each cylinder.

Abstract: Methods and systems are provided for reliably providing a prognosis of the life-expectancy of a vehicle battery. A state of degradation of the battery is predicted based on a rate of convergence of a metric, that is derived from a sensed vehicle operating parameter, towards a defined threshold, determined based on past history of the metric. The predicted state of degradation is then converted into an estimate of time or distance remaining before the component needs to serviced, and displayed to the vehicle operator. Vehicle control and communication strategies may be defined with respect to the predicted state of degradation.

Abstract: A system includes a processor configured to receive a set of user attribute preferences for a trip. The processor is also configured to determine a plurality of trip routes, the routes having variance in a value for at least one user attribute preference as compared to other of the routes. The processor is further configured to present the plurality of routes in a selectable manner, including displaying an attribute value associated with each route and implement navigation for a selected route.

Abstract: A system includes a processor and a memory. The memory stores instructions executable by the processor to, based on a vehicle destination, identify a diagnostic condition and a specified operating pattern of a vehicle component that includes at least one of vehicle propulsion, braking, and steering. The memory stores instructions executable by the processor to operate the vehicle based on the vehicle component and the operating pattern.

Abstract: A vehicle computer includes a memory and a processor programmed to execute instructions stored in the memory. The instructions include receiving a wheel speed from a wheel speed sensor, receiving a vehicle speed from a vehicle speed sensor, determining a mean vibration magnitude in accordance with the wheel speed and the vehicle speed, and detecting a vibrating vehicle wheel based on the mean vibration magnitude.

Abstract: Systems and methods for evaluating whether or not degradation of an engine air intake air filter is present based on a pressure drop across the air filter are presented. In one example, a mean and standard deviation of a pressure drop across an air filter are a basis for indicating whether or not the air filter is degraded. Further, the mean and standard deviation are a basis for estimating a useful life cycle of the air filter.

Abstract: A vehicle computer includes a memory and a processor programmed to execute instructions stored in the memory. The instructions include receiving a wheel speed from a wheel speed sensor, receiving a vehicle speed from a vehicle speed sensor, determining a mean vibration magnitude in accordance with the wheel speed and the vehicle speed, and detecting a vibrating vehicle wheel based on the mean vibration magnitude.

Abstract: Methods and systems are provided for converting an asymmetric sensor response of an exhaust gas sensor to a symmetric response. In one example, a method includes adjusting fuel injection responsive to a modified exhaust oxygen feedback signal from an exhaust gas sensor, where the modified exhaust oxygen feedback signal is modified by transforming an asymmetric response of the exhaust gas sensor to a symmetric response. Further, the method may include adapting parameters of an anticipatory controller of the exhaust gas sensor based on the modified symmetric response.

Abstract: A method is provided, comprising terminating a pressure rise portion of an engine-off natural vacuum test based on an initial rate of change of a fuel system pressure upon sealing a fuel system; and initiating a vacuum portion of the engine-off natural vacuum test responsive to suspending the pressure rise portion. The initial rate of change may indicate a likelihood of the pressure rise portion reaching a pressure rise threshold. In this way, the vacuum portion of the test may be initiated earlier, increasing the likelihood of a conclusive result being obtained during a test time limit.

Abstract: Methods and systems are provided for reliably prognosing a vehicle component, such as a vehicle battery or an intake air filter. A state of degradation of the component is predicted based on a metric that is derived from a sensed vehicle operating parameter, the parameter selected based on the component being diagnosed, as well as based on past driving history and future driving predictions. The predicted state of degradation is then converted into an estimate of time or distance remaining before the component needs to serviced, and displayed to the vehicle operator.

Abstract: A diagnostic method for a capacitive humidity sensor comprising a heater, and a capacitance-sensing element that individually identifies heater, temperature-sensing element, or capacitance-sensing element degradation. By this method, individual elements of the sensor may be replaced or compensated for to allow for further operation.

Abstract: A computer determines that a rate of travel value for a route segment being traversed by a first vehicle exceeds a predetermined threshold. A maneuver is planned for the first vehicle to depart from the route segment based on collected vehicle operating data from one or more second vehicles previously traversing the route segment. The first vehicle is instructed to execute the maneuver to depart the route segment.

Abstract: A vehicle system includes a processor having a memory. The processor is programmed to predict a vehicle key-on time based on a next destination of a vehicle. The processor is further programmed to request, at a predetermined amount of time before the key-on time, optimization data from a remote server.

Abstract: Methods and systems are provided for processing of an on-board diagnostic (OBD) test dataset, and transferring parameters of a curve fit to the processed data to an off-board location. In one example, a method may include performing an evaporative emissions system diagnostic test, fitting a curve to at least a part of the data, transferring parameters of the curve fit, along with the start, and end data points to an off-board location for further processing. The on-board controller may adjust engine operating conditions based on signal received from the off-board location after off-board data reconstruction, and analysis.

Abstract: Methods and systems are provided for determining condition of an air filter coupled to an intake passage of an engine system. In one example, a method may include estimating a resistance of the air filter based on a manifold air charge value. The manifold air charge value may be either a mass air flow or a manifold air pressure.

Abstract: A computer that includes a processor and memory that stores instructions executable by the processor, so that the computer is programmed to: instruct a host vehicle to follow a leader vehicle; monitor driving behavior of the leader vehicle; and instruct the host vehicle to cease following the leader vehicle based on an abnormal driving action of the leader vehicle.