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 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.