故障现象一辆型号为CJY6470E猎豹越野车(采用4G64S4M发动机),行驶里程约25.4万km,出现发动机工作时异响和抖动,发动机故障灯亮,发动机个别气缸工作不良,排气管有突突声的现象。故障诊断承修该车后,首先起动发动机验证故障现象,发现确实存在上述故障。接着连接故障检测仪调取故障代码,故障代码的含义是空气流量传感器信号不良。经过对此故障代码分析,认为即使空气流量传感器信号不良,但并不至于引起个别气缸不工作。于是决定用点火正时枪逐缸进行检查。发现2缸、3缸和4缸发光强度匀称,说明没有断电的现象,只有1缸有断电的现象,说明1缸 Fault phenomenon A model CJY6470E Cheetah sport utility vehicle (using 4G64S4M engine), mileage of about 254,000 km, the engine when the abnormal sound and jitter, the engine fault light, the engine cylinder work poor, the exhaust pipe bursts sound phenomenon . After troubleshooting the car repair, first start the engine to verify the failure phenomenon and found that the above-mentioned failure does exist. Then connect the fault detector to retrieve the fault code, the meaning of the fault code is the air flow sensor signal is bad. After this fault code analysis, even if the air flow sensor signal is not good, but does not cause individual cylinders do not work. So decided to use ignition timing cylinder by cylinder inspection. Found 2 cylinder, 3 cylinder and 4 cylinder symmetrical luminous intensity, indicating that there is no power outage phenomenon, only 1 cylinder power off phenomenon, indicating a cylinder