The lower temperature requirement for the operating environment of the rail snow removal vehicle is -35. The diesel engine and generator set in the non-operating state are generally in the shutdown state and the shutdown time cannot be determined. Docked at the station line and the backup line, there is no guarantee that an external power supply can be provided before starting. Based on the above conditions, the main factors affecting the low temperature cold start performance of the rail snow removal vehicle include the following aspects: the suction temperature and the ambient temperature in the cylinder are too low (may reach -35 ), resulting in a drop in the temperature at the end of compression, poor ignition performance, and stagnation of ignition A longer period of time leads to poor cold start performance; with the decrease of ambient temperature, the viscosity of the engine lubricating oil increases and the fluidity becomes poor, which increases the rotational resistance of the crankshaft and reduces the starting performance of the engine. With the decrease of ambient temperature, the capacity and terminal voltage of the starting battery will decrease, which will inevitably lead to the reduction of the starting torque of the engine, thus directly affecting the starting performance of the engine. Since the output end of the engine is connected to the transfer case and the hydraulic pump, as the ambient temperature decreases, the viscosity of the hydraulic oil increases, and the starting resistance of the drive pump increases, resulting in an increase in the starting resistance of the engine and a decrease in the starting performance of the engine.