Control method and control device for internal combustion engine

A control device for an internal combustion engine comprising:

• the internal combustion engine having an electric heating catalyst in an exhaust system;
• and
• an engine controller configured to start preheating of the electric heating catalyst by energizing the electric heating catalyst before starting the internal combustion engine, and perform the preheating until an estimated temperature of the electric heating catalyst, which is sequentially estimated, reaches a predetermined temperature,
• wherein the engine controller is further configured to, when information on the estimated temperature is lost during the preheating due to loss of power of the engine controller, forbid energization of the electric heating catalyst until a cooling period necessary for temperature of the electric heating catalyst to fall elapses after recovery of the power of the engine controller.