Common faults 1: when the fuel door and direction are killed, the chassis has abnormal sound. Reason for diagnosis: in order to prevent the driver from killing the direction of the driver, Nissan car installed a limit screw at the front of the chassis exhaust pipe. The above situation may be something to hit the chassis of the front exhaust pipe, so that the cover is loose. Solution: a slight collision only needs to top the car to tighten the screw. The limit screw cap is worn out or the limit nut is broken, so the limit nut or butter is needed to be replaced.