US Patent 7100565 DOD throttling and intake control

A throttling and intake control system transitions between activated and deactivated modes in a displacement on demand engine. The throttling and intake control system includes an intake manifold pressure sensor that generates an intake manifold pressure signal and a controller that calculates a pressure window based on the manifold pressure and an engine speed signal. The controller transitions the engine from the activated mode to the deactivated mode when the measured intake manifold pressure is greater than the maximum limit of the pressure window. The controller transitions the engine from the deactivated mode to the activated mode when the intake manifold pressure is less than the lower limit of the pressure window.