Abstract: In the automobile engine management system, the injector driven by electromagnetic pulse is a very important part. Vertical injection moulding machine is mainly used in the injection moulding station of the pre-assembled products of injector in the assembly line of injector. The injection moulding machine mainly includes injection system, clamping system, hydraulic transmission system, electrical control system, lubrication system, heating and cooling system, safety monitoring system, etc. In the daily production process, the main faults of the hydraulic transmission system of injection moulding machine are incomplete injection moulding parts, overload protection of the motor of injection moulding machine, turning head of injection moulding machine, pressure of injection moulding machine system, etc. In this paper, the faults with high failure rate and long maintenance time are analyzed, and the phase is given. The corresponding solutions provide a reference method for the fault diagnosis and treatment of such injection moulding machine, which has a good practical application value in engineering.