Abstract: In this paper, for the problem of click abnormal noise in a pickup truck at idle speed, using Hilbert transform and envelope analysis methods. By first analyzing the band-pass filtering and envelope of the measured signals, the abnormal noise frequency composition is 800～1 000 Hz and obtaines an excitation frequency of 25 Hz. Then, the noise conforming to the frequency characteristics is checked and the main transmission path is determined to be injector-fuel pipe-pipe clamp-body. Finally, through the analysis, it is considered that the damping pipe clamp is the most simple and easy to use, and the real verification of the scheme is carried out, the click abnormal noise disappears, and the effect is good.

Key words: abnormal noise diagnosis; band-pass filtering; envelop analysis; transmission path

摘要： 文章针对某皮卡怠速车内哒哒异响问题，采用希尔伯特变换与包络分析的方法，首先 通过对测量信号带通滤波和包络进行分析，确定了异响频率成分为 800～1 000 Hz，得到激励 频率为 25 Hz；然后对符合频率特性的噪声进行排查，确定了喷油器－燃油管－管夹－车身为 主要传递路径；最后通过分析认为采用减振管夹最为简单易行，并对该方案进行了实物验证， 哒哒异响消失，效果较好。

关键词: 异响诊断；带通滤波；包络分析；传递路径