Patent ID: 7934370

Claim:
A control method of a vehicle including an internal combustion engine, an exhaust gas control catalyst that purifies exhaust gas discharged from the internal combustion engine, fuel injecting means for injecting fuel into the internal combustion engine, vehicle speed detecting means for detecting a vehicle speed, and automatic shutting off means for shutting off the internal combustion engine when the vehicle speed detected by the vehicle speed detecting means is in a first low vehicle speed region, an electric power/power input/output apparatus which is connected to a driveshaft and an output shaft of the internal combustion engine, and outputs at least some power from the internal combustion engine to the driveshaft with input/output of power and electric power, an electric motor that selectively inputs and outputs power to and from the driveshaft, and a power storing device that selectively supplies and receives electric power to and from the electric power/power input/output apparatus and the electric motor, the control method comprising the steps of: i) when a predetermined catalyst degradation condition is satisfied when a predetermined fuel cut condition is satisfied, executing control to suppress catalyst degradation that keeps the internal combustion engine firing without cutting off the injection of fuel by the fuel injecting means when the vehicle speed detected by the vehicle speed detecting means is outside of a second low vehicle speed region set based on an operating state of the vehicle, wherein a parameter relating to the operating state of the vehicle includes a state of the power storing device; and ii) executing fuel cut control that stops the internal combustion engine from firing by cutting off the injection of fuel by the fuel injecting means when the vehicle speed detected by the vehicle speed detecting means is in the second low vehicle speed region while the control to suppress catalyst degradation is being executed.