Control method and control device for internal combustion engine

An internal combustion engine (1) is a spark-ignition internal combustion engine provided with a turbocharger (2) and an exhaust gas recirculation device, and operates on the basis of a stoichiometric air-fuel ratio by performing exhaust gas recirculation even in a high-load region including the highest output operating point. When the highest output operating point is requested (step 1), the intake air density (rho) is calculated on the basis of intake air information (step 2) such as atmospheric pressure and outside air temperature (step 3), and compared with a predetermined density threshold value (rho #) (step 4). When the intake air density (rho) is less than or equal to the density threshold value (rho #) on plateau or the like, the exhaust gas recirculation rate is set to 0 (step 6). As a result, a higher maximum output can be obtained compared with when exhaust gas recirculation is performed. 内燃机(1)是具有涡轮增压器(2)以及排气回流装置的火花点火式内燃机，在包含最高输出运转点在内的高负荷区域也进行排气回流，由此进行基于理论空燃比的运转。在请求最高输出运转点的情况下(步骤1)，基于大气压、外部空气温度等进