Turns over but wont start???

[breakbredquick]

Alright fellas i thought i fixed every possile thing wrong with my 1990 3.8 ltr Buick Riviera but obviously not. Heres the jist of things ive replaced with new parts, MAF Sensor, o2 sensor, plugs, wires, CPS Sensor, Oil, Oil filter, and fuel filter. Now the damn car was starting like a champ for a few weeks and now it wont start up immediatley, and just wil crank. To get her started i usually have to turn the key on and off waiting about 5 secs in between each cycle and usually takes about 10 cycles, sometimes it takes 5 and sometimes it takes 30 cycles. Dont get me wrong im not trying to point u in the direction of fuel pump as when i did test the fuel pressure it read 38-40psi with key on and/or engine started, keep in mind this pressure test was generated after i got it started and drove it to a fuel pressure tester. Now when i turn the key on i dont hear the fuel pump working, yet sometimes i do. But even when i do hear it the car does not want to start. Im lost as to why even when i hear the pump the car wont start! initially i assumed it was the fuel pump but the pressure is somewhat there, not were it should be from my understanding, nonetheless it is still there and enough to start the car. The car seems to die in the worst places as well after i get it started, usually in the middle of the intersection wich is not a good place and im illegal driver with no license so some quick help here would be great. Im gonna try some fuel injection cleaner but im pretty sure thats not my solutuion so anything u guys might have would be great.l

[maxwedge]

Check the fp on the first start when the problem exists, normal diagnostics.

[jase386]

check the fuel pressure regulator. My friends regal had the same problems, nothing he did would allow it to start up, it would wind and wind, but no start. The fifth mechanic changed the fuel pressure regulator and up she started..