Abstract: Systems and methods for improving emissions of an internal combustion engine are presented. In one example, engine crankshaft acceleration is a basis for estimating engine air-fuel ratio during engine starting when output of an oxygen sensor may be unavailable. An actual engine air-fuel ratio may be adjusted in response to the estimated engine air-fuel ratio.

Abstract: Embodiments for reactivating a catalyst are provided. In one example, a method for reactivating a catalyst coupled to an engine comprises when the engine is restarted following deactivation, adjusting a degree of fuel enrichment based on an engine off duration and an engine air amount during the restart.

Abstract: Systems and methods for improving emissions of an internal combustion engine are presented. In one example, engine crankshaft acceleration is a basis for estimating engine air-fuel ratio during engine starting when output of an oxygen sensor may be unavailable. An actual engine air-fuel ratio may be adjusted in response to the estimated engine air-fuel ratio.

Abstract: Methods and systems are provided for modeling an oil dilution qualitative indicator based on an integrated difference between a commanded air-to-fuel ratio and an engine air-to-fuel ratio as determined via an oxygen sensor, cumulative cold engine temperature operating duration, and fuel injection characteristics (timing, duration, number of injections) allowing fuel injection timing modifications that minimize oil dilution when the oil dilution qualitative indicator is greater than a threshold level.

Abstract: Air/fuel imbalance monitoring systems and methods for monitoring air/fuel ratio imbalance of an internal combustion engine are disclosed. In one embodiment, adjusting engine operation responsive to cylinder air/fuel imbalance based on a determined total number of instances where sensed peak-to-peak exhaust air-fuel ratios differentials are less than a threshold normalized to a total number of peak-to-peak oscillations. The approach can be used to indicate air/fuel ratio imbalances between engine cylinders.

Abstract: Air/fuel imbalance monitoring systems and methods for monitoring air/fuel ratio imbalance of an internal combustion engine are disclosed. In one embodiment, adjusting engine operation responsive to cylinder air/fuel imbalance based on a determined total number of instances where sensed peak-to-peak exhaust air-fuel ratios differentials are less than a threshold normalized to a total number of peak-to-peak oscillations. The approach can be used to indicate air/fuel ratio imbalances between engine cylinders.

Abstract: Methods and systems are provided for modeling an oil dilution qualitative indicator based on an integrated difference between a commanded air-to-fuel ratio and an engine air-to-fuel ratio as determined via an oxygen sensor, cumulative cold engine temperature operating duration, and fuel injection characteristics (timing, duration, number of injections) allowing fuel injection timing modifications that minimize oil dilution when the oil dilution qualitative indicator is greater than a threshold level.

Abstract: Embodiments for reactivating a catalyst are provided. In one example, a method for reactivating a catalyst coupled to an engine comprises when the engine is restarted following deactivation, adjusting a degree of fuel enrichment based on an engine off duration and an engine air amount during the restart.

Abstract: The present invention provides a throttle position sensor for a motorcycle including a handlebar having an end. The throttle position sensor includes a rotor having a first end and a second end. The rotor is positioned within the handlebar and rotated relative to the handlebar. The second end is closer than the first end to the end of the handlebar. The throttle position sensor also includes a sensor operable to detect rotation of the rotor relative to the handlebar and generate a signal corresponding to the rotation of the rotor relative to the handlebar. The throttle position sensor further includes at least one electrical conduit passing into the rotor from the first end. The at least one electrical conduit is routed through the rotor and is accessible from the second end of the rotor.

Abstract: The present invention provides a throttle position sensor for a motorcycle including a handlebar having an end. The throttle position sensor includes a rotor having a first end and a second end. The rotor is positioned within the handlebar and rotated relative to the handlebar. The second end is closer than the first end to the end of the handlebar. The throttle position sensor also includes a sensor operable to detect rotation of the rotor relative to the handlebar and generate a signal corresponding to the rotation of the rotor relative to the handlebar. The throttle position sensor further includes at least one electrical conduit passing into the rotor from the first end. The at least one electrical conduit is routed through the rotor and is accessible from the second end of the rotor.