fuel pressure regulator
Fuel filter may be plugged, foward of tank on driver frame rail. Check fuel pressure w gauge set minimum 32 psi - 65psi is optimal under 40 may start stall or have runability issues (misfire). If you replaced pump w cheap after market pump,just because it shiny dont mean its any good the chinese clap cheap crap together cause its not going in their car
If pump runs and no pressure feed line from pump to output could be detached inside tank. Cycle key wait for pump to stop listen for dripping inside tank.
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