Have the high pressure natural gas, through 3 times of pressure reduction, proportionally output fuel upon the negative pressure reduction, proportionally output fuel upon the negative pressure under the different working conditions of the engine, a high voltage solenoid valve, low voltage solenoid valve and pressure sensor are placed inside.

Have the high pressure natural gas, through 3 times of pressure reduction, proportionally output fuel upon the negative pressure reduction, proportionally output fuel upon the negative pressure under the different working conditions of the engine, a high voltage solenoid valve, low voltage solenoid valve and pressure sensor are placed inside.