{HEAD ~ A drive mechanism}, which may include a stepper motor, intermittently rotates {TAIL ~ the fuel distributor shaft} so that the shaft discharge port dwells in registration with one of the fuel distributing passages at the time a pressurized pulse of fuel is discharged through the shaft discharge port 
intermittently rotates
{ HEAD ~ A drive mechanism } , which may include a stepper motor , intermittently rotates { TAIL ~ the fuel distributor shaft } so that the shaft discharge port dwells in registration with one of the fuel distributing passages at the time a pressurized pulse of fuel is discharged through the shaft discharge port
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH