Yes fuel pressure is important, but fuel volume is often overlooked. Forget the spec but remove fuel line after filter somewhere convenient and put a glass jar inside, crank engine and time it, you should have a certain amount of fuel for the specified time. Or remove fuel filter and if you have in line fuel pressure tester, (I added a shut off valve on the side of mine) simply open while cranking. Now you have pressure, volume readings and fuel sample. Check at seperate times of course. May or may not be the cause but simple and fast check, if ok, move on with diagnostics.