METHOD FOR CONTROLLING INTERNAL COMBUSTION ENGINE AND DEVICE FOR CONTROLLING INTERNAL COMBUSTION ENGINE

An internal combustion engine control method controls an internal combustion engine equipped with an exhaust gas temperature variation factor unit that causes variations in the temperature of exhaust gas of the internal combustion engine, an exhaust heat recovery device that is disposed in an exhaust passage downstream of the exhaust gas temperature variation factor unit in the flow direction of the exhaust gas and that recovers the heat from the exhaust gas into a refrigerant that cools the internal combustion engine, and a refrigerant flow rate adjustment unit that adjusts the flow rate of the refrigerant that passes through the exhaust heat recovery device. The internal combustion engine control method comprises estimating a boiling margin, which is a parameter related to the thermal margin when the refrigerant boils in the exhaust heat recovery device, and determining whether to execute a boiling avoidance process in accordance with the boiling margin.