Abstract: A system and method for selecting the operating mode of a variable displacement engine includes a controller with a stored engine map, an engine speed sensor, and an inferred desired fractional manifold vacuum which would be required for the engine to operate on a fractional number of cylinders, given the driver's current torque requirements, a specific emissions calibration, and environmental conditions, deriving this inferred desired fractional manifold vacuum from stored information and assorted engine sensor input. The system compares its inferred desired fractional manifold vacuum and current engine speed to one or more stored maps of inferred desired fractional manifold vacuum versus engine speed in order to decide which operating mode should be selected.

Abstract: An Electronic Engine Controller (EEC) controls the operation of an electronically controlled throttle. The EEC generates a predicted desired throttle angle value as a function of upstream and downstream air pressure values, an air temperature value and a desired airflow value. A predicted actual throttle angle value is generated as a function of the upstream and downstream air pressure values, an air temperature value and an actual airflow value. A throttle angle difference value is generated as a function of the difference between the predicted desired throttle angle value and the predicted actual throttle angle value. A PID controller is employed to generate a throttle angle change value. The throttle angle change value is then added to the predicted desired throttle angle change value to generate a throttle angle control value, indicative of a position for said throttle. The throttle angle is then altered to a position corresponding to the throttle angle control value.

Abstract: A system for selecting the operating mode of a variable displacement engine includes a vacuum analyzer, a flow analyzer, and a controller for determining whether the variable displacement engine should be operated on a fractional number of cylinders. The vacuum analyzer generates a vacuum recommendation signal indicating whether a fractionally operating variable displacement engine can accommodate the inferred desired fractional manifold vacuum with respect to a desired torque and a specific emissions calibration. The flow analyzer generates a flow recommendation signal indicating whether a fractionally operating variable displacement engine can accommodate a desired mass air flow and a desired exhaust gas recirculation flow with respect to a desired torque, a specific emissions calibration, and environmental conditions. The controller evaluates the vacuum and flow recommendation signals no determine the operating mode of the engine.

Abstract: An apparatus for determining a number of cylinders to operate in a variable displacement engine includes a signal representative of air charge temperature, a signal representative of barometric pressure, a desired mass air flow evaluator, a maximum mass air flow evaluator, a desired exhaust gas recirculation flow evaluator, a maximum exhaust gas recirculation flow evaluator, and a controller. The controller compares the desired mass air flow to the maximum mass air flow, generating a mass air flow error signal if desired mass air flow error exceeds maximum mass air flow error. The controller also compares the desired exhaust gas recirculation flow to the maximum exhaust gas recirculation flow, generating an exhaust gas recirculation flow error signal if desired exhaust gas recirculation flow exceeds maximum exhaust gas recirculation flow.

Abstract: A system for controlling the transient torque output of a multicylinder, variable displacement, spark-ignited, fuel injected automotive internal combustion engine during periods when the effective displacement of the engine is being changed includes a spark timing controller, a throttle controller for positioning an intake air throttle, an engine cylinder operator for deactivating and reactivating at least some of the engine's cylinders, and an engine controller having a processor for selecting the number of cylinders for operation and for operating the spark timing controller, the throttle controller, and the cylinder operator so that during any transition from operation with a first number of activated cylinders to operation with a second number of activated cylinders, the processor will alter the spark advance and control the amount of air entering the engine cylinders so that the torque output of the engine will remain relatively unchanged during the transition.

Abstract: A system for controlling the flow of air entering the intake manifold of a multicylinder variable displacement internal combustion engine installed in a vehicle having a driver-operable accelerator control includes an accelerator control position sensor for determining the operating position of the accelerator control and for generating an accelerator control position signal indicating such position, as well as an engine speed sensor for determining the speed of the engine and for generating an engine speed signal indicating such speed. The present system further includes an engine cylinder operator for deactivating and reactivating at least some of the cylinders and an electronically controlled throttle valve positioned in the intake manifold of the engine so as to control the amount of air entering the engine's cylinders.

Abstract: A system for synchronously activating cylinders of a multicylinder, fuel injected, four stroke cycle internal combustion engine, includes a valve operator for deactivating intake and exhaust valves associated with the cylinders and a controller for selecting a cylinder to be deactivated, as well as a timing mechanism for determining when the selected cylinder is operating during intake events. The controllers directs the valve operator to begin deactivating the valves of a selected cylinder during a predetermined intake event, with the valve operator completing the deactivation by a time not later than the beginning of the next exhaust event.

Abstract: A system for selecting the number of cylinders to be operated in a multi-cylinder variable displacement internal combustion engine installed in a vehicle having a driver operable accelerator control includes an accelerator control position sensor for determining the operating position of the accelerator control and an engine speed sensor for determining the speed of the engine, as well as a processor containing stored values for engine load as functions of engine speed and accelerator position and also engine load at wide open throttle. The processor infers engine load based on the accelerator control position and engine speed then selects the number of cylinders of the engine to be operated based at least in part of a comparison of the inferred engine load and the maximum possible load at the same engine speed.

Abstract: A system for predicting cylinder air charge for a variable displacement internal combustion engine operating in a transition from a first number of activated cylinders to a second number of activated cylinders includes a throttle sensing system for determining the effective flow area of the air intake passage of the engine and for generating a signal corresponding to the area, an engine speed sensor for determining the speed of the engine and for generating a signal corresponding to the speed, an airflow sensor for determining the instantaneous mass airflow into the engine and for generating a signal corresponding to the airflow, and a controller for receiving the speed, flow area, and mass airflow signals and for calculating the mass of air admitted to each engine cylinder during its intake stroke, based upon the values of the signals.

Abstract: A system for controlling the transient torque output of a multicylinder, variable displacement, spark-ignited, fuel injected automotive internal combustion engine during periods when the effective displacement of the engine is being changed includes a spark timing controller, a throttle controller for positioning an intake air throttle, an engine cylinder operator for deactivating and reactivating at least some of the engine's cylinders, and an engine controller having a processor for selecting the number of cylinders for operation and for operating the spark timing controller, the throttle controller, and the cylinder operator so that during any transition from operation with a first number of activated cylinders to operation with a second number of activated cylinders, the processor will alter the spark advance and control the amount of air entering the engine cylinders so that the torque output of the engine will remain relatively unchanged during the transition.