Fault symptoms when engine starts cold start (shift lever at P position), engine idling fast and slow, commonly known as "touring car". This situation often occurs in the emission control system from "open loop" to "closed loop", especially when the ambient temperature is higher. The cause of the fault is due to the different fuel injection quantity of the engine during the "open loop" and "closed loop" operation. The elimination method can eliminate this phenomenon by installing a new flash point program in the engine electronic control unit. After the installation of the new flash program, the following changes will be made: one is the increase of closed loop delay; and the two is to reduce the amount of fuel injection from open loop to closed loop. Precautions (1) the new flash point program starts in the CD disk of general maintenance technology department, starting from No. 16 CD disk. (2) the flash point program of the new car has been installed in the PCM through the Techline instrument.