Patent ID: 7770562

Claim:
A fuel delivery system for an internal combustion engine, comprising: a first fuel injector configured to deliver fuel to a cylinder of the engine; a second fuel injector configured to deliver fuel to the cylinder of the engine; a fuel storage tank; a fuel delivery circuit including a first fuel passage fluidly coupling the fuel storage tank to the first fuel injector and a second fuel passage fluidly coupling the first fuel passage to the second fuel injector; a fuel pump configured to supply fuel from the fuel storage tank to the fuel delivery circuit; a pressure relief valve arranged along the second fuel passage and located upstream from the second fuel injector, said pressure relief valve configured to: close the second fuel passage when fuel is supplied from the fuel storage tank to the fuel delivery circuit at a first pressure produced by the fuel pump; and open the second fuel passage when fuel is supplied from the fuel storage tank to the fuel delivery circuit at a second pressure produced by the fuel pump; a control system configured to: during a first operating condition, operate the fuel pump to supply fuel from the fuel storage tank to the fuel delivery circuit at the first pressure while only operating the first fuel injector to deliver to the cylinder the fuel received from the fuel storage tank; and during a second operating condition, operate the fuel pump to supply fuel from the fuel storage tank to the fuel delivery circuit at the second pressure while operating the first and the second fuel injectors to deliver to the cylinder the fuel received from the fuel storage tank.