Abstract: An electric motor or generator is used to spin the vehicle's internal combustion engine while the engine is not running, in order to draw a vacuum within the vapor control system. Vacuum bleed off is then monitored to determine if an unacceptable condition in the control system may exist. The evaporative fuel emissions test may be conducted either while the vehicle is at rest or while under way in an electric drive mode of operation.

Abstract: An electric motor or generator is used to spin the vehicle's internal combustion engine while the engine is not running, in order to draw a vacuum within the vapor control system. Vacuum bleed off is then monitored to determine if an unacceptable condition in the control system may exist. The evaporative fuel emissions test may be conducted either while the vehicle is at rest or while under way in an electric drive mode of operation.

Abstract: An electric motor or generator is used to spin the vehicle's internal combustion engine while the engine is not running, in order to draw a vacuum within the vapor control system. Vacuum bleed off is then monitored to determine if an unacceptable condition in the control system may exist. The evaporative fuel emissions test may be conducted either while the vehicle is at rest or while under way in an electric drive mode of operation.

Abstract: A method is provided for controlling an engine in a vehicle to facilitate determination of engine position sensor correction factors. The vehicle includes a motor, which is operatively connected to the engine, a sensor configured to detect engine position, and a controller, which is in communication with the engine, the sensor and the motor. It is determined when an engine shutdown is requested, for example, when the controller commands the vehicle to be powered by the motor. It is next determined whether engine position sensor correction factors are known. If they are, the engine control routine is stopped. If the correction factors are not known, fuel to the engine is discontinued, and the motor is employed to spin the engine at an approximately constant speed. The engine position sensor correction factors can then be determined while the engine is rotating in a defueled state.

Abstract: A method is provided for controlling an engine in a vehicle to facilitate determination of engine position sensor correction factors. The vehicle includes a motor, which is operatively connected to the engine, a sensor configured to detect engine position, and a controller, which is in communication with the engine, the sensor and the motor. It is determined when an engine shutdown is requested, for example, when the controller commands the vehicle to be powered by the motor. It is next determined whether engine position sensor correction factors are known. If they are, the engine control routine is stopped. If the correction factors are not known, fuel to the engine is discontinued, and the motor is employed to spin the engine at an approximately constant speed. The engine position sensor correction factors can then be determined while the engine is rotating in a defueled state.

Abstract: A signal indicating closed throttle position is corrected, through increases and decreases, as a function of an engine's volumetric efficiency, engine speed, application of a vehicle's brake, and the selection of a transmission gear.