一辆北京牌ＢＪ2 12型汽车 ,断开点火开关后 ,发动机不熄火。起初以为是点火开关有问题 ,但更换了一只点火开关后 ,故障仍旧。无奈之下 ,驾驶员只好在停车熄火时拆除蓄电池搭铁线。检修时 ,笔者通过询问得知驾驶员曾调整过该车的快怠速调整螺钉。根据了解 ,笔者找到了故障原因 A Beijing brand BJ2 12 cars, disconnect the ignition switch, the engine does not turn off. Initially thought it was a problem with the ignition switch, but the replacement of an ignition switch, the fault is still. In desperation, the driver had no choice but to remove the battery on the line when the parking stall. Overhaul, I asked through the inquiry that the driver had adjusted the car’s fast idle adjustment screw. According to understand, I found the cause of the malfunction