A Charlie car equipped with three cylinder connected M1. 5.4 EFI engine. The car owner says it is easy to extinguish when the car is fast decelerating. When the vehicle is running normally, the engine will stall if emergency braking occurs. According to the car owner, the fault of the car was due to the maintenance of the front wing fender in other repair factories. After several repair works, no failure was removed. The following tests were carried out as follows: ignition timing, gasoline pressure and activated carbon tank system did not find problems, but also the replacement of idle motor, cleaning throttle, observation data flow, and even replacement of distributor, and so on, failed to work.