| 摘要 |
PURPOSE:To prevent an exhaust system from overheating, by installing a process, which detects a fact that exhaust temperature reaches the setting value and, after the temperature reaches the setting value, installing another process which makes an air-fuel ratio into being overrich by degrees. CONSTITUTION:There is provided with a process detects a fact that exhaust temperature reaches the setting value in an high speed and high load range of engine. After the exhaust temperature reaches the setting value, there is also provided with a process which makes an air-fuel ratio into being overrich by degrees. For a while till the exhaust temperature reaches the setting value in the high speed and high load range of engine, the air-fuel ratio is maintained in an output air-fuel ratio or an economic air-fuel ratio. Thus, an exhaust system is surely preventable from overheating without entailing any damage to drivability, accelerating performance and a specific fuel consumption. |
