Patent ID: 8511275

Claim:
A method for controlling a fuel system of an engine, comprising: measuring a fuel rail pressure in a higher-pressure fuel sub-system portion of the fuel system, the fuel system comprising the higher-pressure fuel sub-system, a lower-pressure fuel sub-system, and a pressure limiting valve for relieving excess pressure in the higher-pressure fuel sub-system; reducing the fuel rail pressure below a threshold required to close the pressure limiting valve by stopping fuel flow in the higher-pressure fuel sub-system, responsive to the fuel rail pressure falling below a desired operating pressure, to reset the pressure limiting valve; and then stopping fuel injection from at least one fuel injector; restarting fuel flow to the engine without disabling the engine if the fuel rail pressure recovers after resetting the pressure limiting valve; and disabling the engine if the fuel rail pressure persists below the desired operating pressure after resetting the pressure limiting valve.