I like behlinlas idea to check fuel pressure with a gauge at the fuel rail schrader valve test port at start up & while your at it, check the pump flow rate over time.
It should pump 1/2 pint/15 seconds.
Fuel pressure is 28psi min running. Mine runs 30-31 engine running & about 29 psi
, before I crank the engine, so I agree 30 psi
, while toward the low end of spec, is plenty to start & run the engine, IF delivery rate is ok.
If delivery rate is low, suspect a restricted fuel filter, fuel line, in tank pump sock, kinks or clogs in the return line from the fuel rail mounted pressure regulator back to the tank, a weak fuel pump, or maybe an under load voltage drop to the fuel pump. So, perhaps consider doing an under load back probe voltage drop test to the pump, at the in trunk inertia switch location, as that'll check most of the wiring to the pump, but not at its tank electrical connector. So if you come to believe you may have a pump electrical connection problem, maybe try a wiggle test on the electrical connector or wiring to it from the inertia switch.
Our fuel pressure regulator is on the fuel rail & is vacuum operated & its diaphragm can leak & cause a rich fuel trim & fuel pressure problems. So disconnect its vacuum line to see if its wet inside with fuel, if so, the diaphragm is leaking, so replace the fpr
More thoughts for consideration, let us know how your trouble shoot goes.