A vehicle includes a direct-start engine and a fuel rail with a threshold
fuel pressure, a transmission having a threshold fluid pressure, and a
fuel delivery system. The system has a controller, a motor having a
shaft, and an integrated pump assembly including a high-pressure (HP)
fuel pump and a low-pressure (LP) fluid pump each connected to the shaft.
Threshold pressures are maintained during the predetermined engine state,
which includes an engine idling and an engine cranking state. A method
for providing stop-and-go functionality in a vehicle having a
direct-start engine includes detecting a current engine state, rotating a
motor shaft to energize a secondary HP fuel pump at a first threshold
pressure during engine cranking, and rotating the shaft to energize an LP
fluid pump at a second threshold pressure during engine idling and engine
cranking. The secondary pumps can also be used when primary pumps are
temporarily inoperable.