Me and my step dad are stumped on this problem. My step dad was driving home from work one day and the fuel pump went out. So he bought a new one and put it in. But he wasn't getting it to crank. So he replaced the distributor cap and button and was getting fire, but truck would still not crank. You could dump a little gas into the intake manifold and truck would start, but not run for longer than 5 secs. So we checked the fuel filter and it was dirty as crap, so we placed that. Tried it again, same problem. Now we are getting pressure from the fuel pressure tester, but it just won't start or stay running. We were told that there may be some kind of fuel regulator reset or something, but we don't know where that would be.

If anyone can give us any help, we'd appreciate it.

 

You are using a fuel injection pressure tester (gauge) thats hooked up to the test port? Whats your pressure readings at (1) KEY ON, (2) WHILE CRANKING, (3) TURNED OFF, (4) 5 MIN AFTER TURN OFF? You cant just push down that little ball on the test port behind the intake manifold and see fuel, it could still be too low of pressure to operate. Do those 4 test with the gauge hooked up and let us know the results and we will get you back up and running again. If you dont have a gauge you can buy one for about 50 bucks at the auto parts store, borrow one from a neighbor or friend, or possibly get a loaner from the autozone or pepboys. I know NAPA wont loan tools.

For more information you may want to search out the threads on fuel problems and CPI injection, there is lots of them.

The fuel pressure regulator (FPR) is inside the intake manifold on the side of the injection unit. You will need a deep 10MM socket to remove the upper intake plenum to get at it. I would test the system before you go in there. Search out the threads on CPI and you will find out how to check for an internal leak, but the gauge is the easiest way. That way you dont go buying anything you dont need. The gauge will tell you if your new pump is bad, or if its leaking, or if its not pumping enough...

 

There isn't a reset on the fuel pressure regulator (FPR). Ohsofly's right. The fuel pressure you're getting is important. I changed my fuel pump and the guy gave me one for a TBI unit instead of a CPI (Vortec). About 40 psi difference.
Are you getting any codes? Even if it won't start some will show up.