I have a 97 z28 w a LT1. It will start almost immediately w the use of starting fluid. Or, if I let it crank in 2-3 intervals of 3-5 seconds it seems to build enough fuel pressure to fire up. Runs like a beast once running. Also if I happen to stall it (clutch is going), it will start right away if I immediately bump the key. But not if I wait any length of time.
I have 42-46 on fuel pressure, and plenty of strong spark. Hooked the noid lights up to injectors, and I get about 2 flashes and then nothing. There are some posts here from 2010 that seem to be on point with my problem, but I could use some more advise. If anyone can help, I'd sure appreciate it.
It's simply not getting it's initial prime to start the car. I'm stuck.

 

Is that the fuel pressure with it running? Does that fuel pressure hold or immediately bleed off after you shut it down?

Does the fuel pump run for a few seconds when you first turn the key to "on"? If so, is it holding the pressure? If not, maybe there's something in the fuel pump relay or ECM?

 

This is the pressure I have when trying to start it. The fuel pump is working, but whatever is wrong, is not allowing the initial fuel prime to start. If I let it crank over a few times for 3-5 seconds it catches and fires right up. Seems to build up enough pressure and Runs strong......until I shut it off and let it sit for 5 mins. The fuel doesn't seem to be bleeding off. I hooked my noid light up and at initial cranking it catches 2-3 pulses.... then nothing.

 

Check the fuel pump relay. Mine was doing the same thing. Relay was not actuating immediately when the key was turned.

 

It starts after cranking because of the oil pressure switch. It's parallel to the relay so with the engine having oil pressure you don't rely on the relay.