故障现象一辆福特野马车,搭载2.3T发动机,累计行驶里程约为6 300 km,车主反映,行驶过程中仪表盘上防侧滑指示灯、安全气囊指示灯偶尔点亮,并且提示“斜坡起步辅助不可用”(图1)。故障诊断接车后首先试车验证故障现象,起动发动机,发动机顺利起动。观察仪表盘,没有故障灯点亮,尝试多次起动发动机,仪表盘出现上述信息提示。将发动机熄火,发动机室内有时传来“嗒嗒嗒”的异响,经多次试车确认,异响来源于节气门阀板作动的声音。另外还发现,发 Fault phenomenon A Ford Mustang, equipped with 2.3T engine, the cumulative mileage of about 6 300 km, the owner reflects the anti-slip indicator on the dashboard during driving, airbag indicator light occasionally lit, and prompt Starting aid is not available “(Figure 1). Troubleshooting After the first test car to verify the fault phenomenon, start the engine, the engine started smoothly. Observe the dashboard, no fault light lit, try to start the engine several times, the dashboard appears the above message. The engine flameout, the engine room sometimes came ”Dazi Dabi " abnormal sound, after many tests confirmed that the abnormal sound from the throttle valve action sound. Also found that hair