When I go to start my car it cranks over awhile before it starts. I think maybe the fuel pressure relay or the oil pressure sending unit but maybe the fuel pump. I get no fuel pressure at all when I turn the ignition on but if I crank it after awile it shoots up to 42-3 lbs on the gauge. If I disconect the relay it still does the same thing. Once it is running it runs fine no hesitations or anything. It also threw a code 54.

My mechanic is adament it is a fuel pump but I'm not so sure. He thinks the pump is weak so it takes longer to prime but I thought I would see a gradual rise in the fuel pressure while it is cranking if that was it.

It's an 86 305 TPI motor.

 

It wouldn't keep running if it was the oil pressure switch.

Sounds more like the timed relay, although I did have a non-3rd gen EFI in-tank pump car that did pretty much what you're describing. The check valve in the pump was bad.

What happens to fuel pressure after you turn the engine off?

 

It holds steady at around 43 lbs. It doesn't bleed off at all.