Abstract: Abnormal sound of engine is one of the common engine faults, which will affect the comfort, power and safety of the vehicle. Common abnormal engine sound is "tutu""dang dang""da da"etc. In order to diagnose the fault cause and location of different noises more quickly and accurately, this paper analyzes the formation mechanism and logical relation of different noises one by one from the frequency、size and location. The rule of quick maintenance for different abnormal sounds is summarized. The steps and ideas of troubleshooting are illustrated by practical cases, which improves the timeliness and accuracy of the daily maintenance of abnormal engine noise troubleshooting.

Key words: Abnormal sound of the engine; Typical faults; Frequency of tone; Location of noise

摘要： 发动机异响是发动机的常见故障之一，会同时影响汽车的舒适性、动力性和安全性。 常见的发动机异响有“突突”“铛铛”“嗒嗒”等，为了更加快捷准确地诊断各异响的故障起 因和位置，文章从异响的频率、大小、发出部位等多方面入手，逐个分析了各种异响的形成 机理和逻辑关联。总结出了针对不同异响的快速检修规律，并利用实际案例阐述了排故的步 骤和思路，为日常的发动机异响排故维修提高了时效性和准确性。

关键词: 发动机异响；典型故障；声调频率；噪声位置