Abstract: Methods and systems are provided for improving the operating range of an electric vehicle having an engine wherein waste heat generated during motor operation is transferred to pre-heat the engine. Engine starting is predicted based on the electrical torque demand of the vehicle relative to the actual and predicted electrical energy consumption of the electric vehicle. Prior to starting the engine to charge a battery of the motor, various engine components are pre-heated in an order that improves vehicle range while also optimizing fuel economy.

Abstract: Methods and systems are provided for estimating ethanol content in fuel and an age of the fuel in a vehicle engine. In one example, a method may include estimating fuel ethanol content and/or fuel age based on fuel temperature, a speed of sound in fuel, and an attenuation co-efficient of an ultrasonic signal in fuel. One or more engine operating parameters may be adjusted based on the estimated fuel ethanol content and fuel age.

Abstract: Methods and systems are provided for estimating ethanol content in fuel, water content in fuel, and an age of the fuel in a vehicle engine. In one example, a method may include estimating fuel ethanol content, water content, or fuel age based on a resonant frequency (f) of pressure pulsations, a change in fuel rail pressure (?p), and a damping coefficient (?) of pressure pulsations in the fuel rail as estimated after a fuel injection or a pump stroke. One or more engine operating parameters may be adjusted based on the estimated fuel ethanol content, water content, and fuel age.

Abstract: Methods and systems for simultaneously operating port fuel injectors and direct fuel injectors of an internal combustion engine are described. In one example, port fuel injection timing is adjusted to reduce particulate matter formation in the engine so that particulate filter loading may be reduced until a time when the particulate filter may be purged.

Abstract: Methods and systems are provided for improving the operating range of an electric vehicle having an engine wherein waste heat generated during motor operation is transferred to pre-heat the engine. Engine starting is predicted based on the electrical torque demand of the vehicle relative to the actual and predicted electrical energy consumption of the electric vehicle. Prior to starting the engine to charge a battery of the motor, various engine components are pre-heated in an order that improves vehicle range while also optimizing fuel economy.

Abstract: Methods and systems are provided for adjusting an amount of water injected upstream of a group of cylinders based on a determined maldistribution of water among cylinders during a water injection event. In one example, a method may include injecting a first amount of water upstream of a first group of cylinders and a different, second amount of water upstream of a second group of cylinders based on operating conditions of the respective cylinder groups. Further, the method may include adjusting water injection and engine operating parameters in response the evaporated and/or condensed portion of water.

Abstract: Methods and systems are described for controlling fuel injection in an engine equipped with a dual injector system including a port injector and a direct injector. A ratio of port injected fuel to direct injected fuel is adjusted based at least on intake valve temperature. The proportion of fuel port injected into a cylinder is increased as the intake valve temperature for the given cylinder increases to improve fuel vaporization in the intake port.

Abstract: Systems and methods for operating an engine that includes a compression ratio linkage for adjusting engine compression ratio are described. The systems and methods provide different ways of diagnosing the presence or absence of engine misfire in response to engine operating regions that may be more or less prone to torsional engine crankshaft vibration. In one example, engine misfire may be determined responsive to force applied to an engine compression ratio changing linkage.

Abstract: Methods and systems are provided for calibrating engine port injectors. After pressurizing a low pressure fuel rail, a lift pump may be disabled and port injector variability may be correlated with a measured fuel rail pressure drop at each port injection event by sweeping injection pressure while maintaining injection voltage, and then sweeping injection voltage while maintaining injection pressure. A port injector variability map learned as a function of injection voltage and injection pressure is then transformed into a map learned as a function of injection current and injection pressure by accounting for injector variability caused due to changes in injector temperature.

Abstract: Methods and apparatus to enable vehicle-to-vehicle guidance and tracking are disclosed. An example method includes transmitting, from a first vehicle, a first message to a second vehicle. The first message requests the second vehicle to become a leader vehicle. The example method further includes receiving a second message from the second vehicle. The second message includes leader information indicative of a travel path of the second vehicle. The example method also includes receiving authorization from the second vehicle for the first vehicle to follow the second vehicle.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, an amount of opening overlap between a plurality of intake valves and a first set of exhaust valves coupled to the first exhaust manifold may be adjusted responsive to a transition from an estimated combustion air-fuel content to a leaner air-fuel content of the blowthrough air on a cylinder to cylinder basis. As one example, the transition may be determined from an output of an oxygen sensor positioned within the first exhaust manifold or an exhaust runner of each of the first set of exhaust valves.

Abstract: Methods and systems are provided for estimating ethanol content in fuel and an age of the fuel in a vehicle engine. In one example, a method may include estimating fuel ethanol content and/or fuel age based on fuel temperature, a speed of sound in fuel, and an attenuation co-efficient of an ultrasonic signal in fuel. One or more engine operating parameters may be adjusted based on the estimated fuel ethanol content and fuel age.

Abstract: Methods and systems are provided for estimating ethanol content in fuel, water content in fuel, and an age of the fuel in a vehicle engine. In one example, a method may include estimating fuel ethanol content, water content, or fuel age based on fuel rail temperature, and two or more of a resonant frequency (f) of pressure pulsations, a change in fuel rail pressure (?p), and a damping coefficient (?) of pressure pulsations in the fuel rail as estimated after a fuel injection or a pump stroke. One or more engine operating parameters may be adjusted based on the estimated fuel ethanol content, water content, and fuel age.

Abstract: Methods and systems are provided for estimating ethanol content in fuel, water content in fuel, and an age of the fuel in a vehicle engine. In one example, a method may include estimating fuel ethanol content, water content, or fuel age based on a resonant frequency (f) of pressure pulsations, a change in fuel rail pressure (?p), and a damping coefficient (?) of pressure pulsations in the fuel rail as estimated after a fuel injection or a pump stroke. One or more engine operating parameters may be adjusted based on the estimated fuel ethanol content, water content, and fuel age.

Abstract: Systems and methods for operating an internal combustion engine that includes an oxygen sensor are described. In one example, a voltage that is applied to a heating element of an oxygen sensor is integrated to determine a resistance of the heating element. The resistance of the heating element is the basis for adjusting voltage applied to the heating element during subsequent engine starts.

Abstract: Methods and systems are provided for coordinating water usage with spark usage based on the effect on an engine torque ratio. Water is injected based on torque ratio at a current spark timing relative to torque ratio at borderline knock to improve the impact of the water injection on the engine performance. Manifold water injection and direct water injected are coordinated based on intake manifold humidity.

Abstract: Methods and systems are provided for adjusting heater power of an oxygen sensor. In one example, a method for an engine includes adjusting heater power of a heating element of the oxygen sensor when the heater power increases by a threshold amount. The method includes subsequently increasing heater power back to a baseline power level responsive to a temperature of the heating element.

Abstract: Methods and systems are provided for determining a dilution of recirculated gases, including blowthrough air, combusted exhaust gas, and fuel vapor, in a split exhaust engine. In one example, the dilution rate may be calculated using a feedforward model that includes determining a pressure differential across a region in an intake passage, mapped engine parameters such as gas temperature, and exhaust valve timing. Engine operations such as spark advance and fuel injection may be adjusted according to the modeled rate to reduce engine knock and improve combustion efficiency.

Abstract: Methods and systems are provided for improved injector balancing. In one example, fuel rail pressure samples collected during a noisy zone of injector operation are discarded while samples collected during a quiet zone are averaged to determine an injector pressure. The injector pressure is then used to infer injection volume, injector error, and update an injector transfer function.

Abstract: Methods and systems are provided for tracking a fuel puddle mass in the intake port of a deactivated engine cylinder. The difference in fuel evaporation rate in the deactivated cylinder intake is accounted for by applying distinct time constant and gain values to a transient fuel compensation model. A fuel vapor content is clipped once the intake vapor pressure in the intake port of the deactivated cylinder reaches a saturation pressure limit.