发动机气缸内的压力和扭矩输出的分配情况是诊断发动机工作状态的一个很重要的参数 ,但这一参数在发动机的运行过程中很难测量。本文讨论了基于发动机模型和瞬态转速测量的气缸故障诊断方法。在发动机瞬态转速波形和气压扭矩波形的基础上 ,定义几个诊断参数VI ,API ,TCI和PCI。利用这些诊断和简单的判断规则 ,可判断发动机各气缸的工作状态 ,并诊断出发动机气缸灭火和供油不足等故障 The distribution of pressure and torque output in the cylinder of the engine is a very important parameter for diagnosing the operating condition of the engine, but this parameter is difficult to measure during the operation of the engine. This article discusses a cylinder fault diagnosis method based on engine model and transient speed measurement. Several diagnostic parameters VI, API, TCI and PCI are defined on the basis of the engine transient speed and pressure torque waveforms. The use of these diagnostic and simple rules to judge the engine can determine the working status of each cylinder, and diagnose the engine cylinder fire and fuel shortage and other failures