JP 5-280394 A (henceforth referred to as patent document 1) discloses a technique of: stopping or cutting off fuel injection of an engine (henceforth referred to as fuel cut-off) when engine rotational speed is above a predetermined fuel cut-off rotational speed while a vehicle is coasting; and restarting fuel injection or recovering from fuel cut-off (henceforth referred to as fuel cut-off recovery) when the engine rotational speed falls below a recovery rotational speed under condition that fuel injection is stopped, wherein the recovery rotational speed is below the fuel cut-off rotational speed. Patent document 1 discloses (1) performing a correction of increasing the fuel cut-off rotational speed at start of fuel cut-off, (2) performing the operation (1) again when fuel cut-off is performed again after fuel cut-off recovery, and (3) repeating the operations (1) and (2) as long as the vehicle continues coasting. This is targeted for suppressing repetition or hunting between fuel cut-off and fuel cut-off recovery at downhill coasting.
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