故障现象一辆2010款丰田威驰车,行驶里程为1.15万km。据驾驶人反映,车辆冷机起动困难,大约需要起动7次～8次才能起动着机,起动着机后,发动机发出“咔嗒”的异响。故障诊断试车发现,故障现象确实存在,且在发动机运转过程中,传来类似气门发出的“咔嗒”声,异响随着发动机转速升高而增大,当发动机转速为1300 r/min～1 800 r/min时异响声明显。用故障检测仪对车辆进行检测,没有发现故障代码。由于发动机能够起动,起动机也能正常工作,于是将故障诊断的重点放在对异响的 Fault phenomenon A 2010 Toyota Vios, mileage of 11500 km. According to the driver, the vehicle cold start difficult, about starting 7 to 8 times to start the machine, start the machine, the engine issued “clicks ” abnormal sound. Fault diagnosis test found that the failure phenomenon does exist, and in the engine operation process, came a similar valve issued “clicks ” sound, abnormal sound increases with the engine speed increases, when the engine speed is 1300 r / The abnormal sound was obvious when min ~ 1 800 r / min. With the fault detector to detect the vehicle, did not find the fault code. Since the engine can start, the starter can work properly, so the fault diagnosis focuses on the abnormal sound