引言　　内燃机瞬时转速信号中蕴含着丰富的发动机工作状态信息，转速的波动与各缸的发火是一一对应的，它综合反映了气缸的工作状态和工作质量，凡可以影响发动机热力循环的故障（如燃油系统故障、进气系统故障等）在瞬时转速信号中均可以反映出来。对于不同的机型，虽然其结 INTRODUCTION The instantaneous engine speed signal contains a wealth of information on engine operating conditions, speed fluctuations and the firing of each cylinder is a one-to-one, which reflects the cylinder’s work status and quality of work, where the engine can affect the thermodynamic cycle of failure Such as fuel system failure, intake system failure, etc.) in the instantaneous speed signal can be reflected. For different models, although its knot