From cold, how far until it stops? Then it starts right back up as if nothing has happened? Then how far until the next "intermission"?
Have the OEM factory rubber fuel lines been replaced? ALL the way to the tank? Usually, ethanol makes them leak first, but if they are in their initial phase of internal separation, they might be blocking flow and then opening back up when the flow/suction stops? Clear or Chrome fuel filter (related to seeing what's going on OR in the filter)?
Might replace the gas cap and also look at the carbon canister as the system should vent into it, if I recall correctly.
CBODY67