Control devices of this type known in the related art include the one disclosed in Japanese Patent No. 2634330.
The controller disclosed in this publication gradually lowers the engine rotation speed instead of immediately lowering it to the idling rotation speed after a travel pedal in a traveling vehicle is released. Namely, it executes speed control on the engine rotation speed so as to prevent the occurrence of cavitation.
Under circumstances in which cavitation tends to occur more readily, such as when the vehicle travels down a long slope, the occurrence of cavitation may not be prevented reliably simply by slowing down the engine rotation speed in response to the release of the travel pedal.