OK so I have a 1989 Irooc-z with the 350 tpi. In the morning it fires right up no hesitation, if I go to the store and come back out it cranks but wont fire until it sits left alone for about 20-30 min.
The car is getting spark, has correct fuel pressure, has new temp sensor. Now when this happens if I spray starting fluid into it, it fires up. I turn it back off, and same thing right away again. I don't know enough about motors to diagnose this, but it sounds to me like something is faulty with the computer that tells it to give fuel when cranking. Please if anyone has any ideas let me know. I don't have 100's of dollars to pay a shop to look at it.

 

Does it have fuel pressure at the very instant that it fails to start up?

Doesn't matter if it has fuel pressure ANY OTHER TIME; gotta determine whether it has it [I[at that exact moment[/I].

A computer is digital in nature. (yes/no, on/off, 0/1, etc.) Digital things usually fail digitally. (works/doesn't) RARELY will such a thing ever fail in some half-cocked mode. I'd dismiss that "explanation" as pretty much a last resort, until AFTER I was sure about the fuel pressure deal, and had run any such issue to ground.

See my signature.

 

Yes the fuel pressure was tested at the exact moment the problem was happening. It had 40+psi, which is where it should be, also had spark at the exact moment... Only thing that would get it to start was spraying starting fluid into it.. I can go out side right now, start my car, turn it off, and it wont start back up