EDPRO Energy Group manufactures the SEQUIN™ sequential propane injection system, which is a gaseous rather than a liquid injection system.

The SEQUIN™ system is only available for Ford Vehicles at this time in the following platforms:

  • 4.6L - Crown Victoria, Police Interceptor, Grand Marquis, Lincoln Town Car
  • 4.6L & 5.4L - F250, F350, E250, E350

Modern propane injection systems today commonly tie-into the OEM engine management system ECU to control the LPG injectors and the SEQUIN™ system does this as well. The SEQUIN™ system starts on gasoline when cold and automatically switches to propane. Because it is a dual fuel system, it will also automatically switch back to gasoline when propane is depleted.

The main difference between the SEQUIN™ system and other competitive systems is that it heats the fuel in the tank to maintain a minimum tank pressure so that the tank supplies propane vapor to the injectors as depicted in the SEQUIN™ 4.6L system specifications. Advantages with the SEQUIN™ system over competitive systems:

  • potential propane "heavy ends" residuals should remain in the fuel tank
  • potential for extreme low temperature operation (far below -40°F) because the car starts on gasoline and only switches to propane when propane fuel pressure is sufficiently high enough.

However, the extra propane heat exchanger, circulation pumps, and fuel lines result in additional costs and complexity for this system and are unnecessary if HD-5 propane motor fuel is used exclusively (rather than commercial heating fuel) and regulator vapor temperatures are controlled to 70°F.