System for controlling engaging and disengaging operations of releasable coupling device placed in automotive power train

摘要

A releasable coupling control system in combination with an electronic engine control unit executable a fuel cutoff mode during vehicle deceleration and re-startable a fuel-supply recovery mode as soon as an engine speed drops below a predetermined threshold value, for controlling engaging and disengaging operations of a releasable coupling device placed in an automotive power train between an engine and drive wheels, comprises a wheel-speed sensor for detecting a drive-wheel speed to generate a drive-wheel speed indicative signal, and a controller being configured to be responsive to the drive-wheel speed indicative signal for moderately releasing the releasable coupling device at a moderate turn-off mode when the drive-wheel speed indicative signal value drops below a first predetermined value, and for quickly releasing the releasable coupling device at a quick turn-off mode when the drive- wheel speed indicative signal value drops below a second predetermined value.