OK......Replaced all the main components in the fuel system just a little over a year ago ...Fuel pump, Spider Injector and Fuel Filter. A few days ago went to start and no go. Listened for Fuel Pump to kick on and nothing so I figured fuel pump relay went out since I never replaced it. Put the new one in and still no go. Figured it was the fuel pump since I did opt to buy the cheaper one when I replaced it. Bought a new Delphi pump and installed along with the harness that came with it and soldered the wire's instead of using the crimp connectors. Hit the switch and nothing. Read in the manual it has a switch built in with the oil pressure switch so I replaced the oil switch too and still nothing. I am at a loss right now.......am I missing something ?? Figured I covered all the bases but to no avail I am missing something I guess. Have any of you had this problem before ??? I need some enlightenment here. Thanks for anyone that can help a Blazer Lovin Fool out.
Had the same problem with my 93 4.3 Vortec Blazer but the oil pressure switch fixed that and my 87 2.8 S15 TBI ...well all I can say 246000 miles and she's still kickin. Can't kill that one .....LOL

 

checked fuses? Does the fuel pump relay even kick on? Voltage getting to the relay? getting to the pump? Possible keyswitch or wiring issue

 

Need you to go to the BF homepage, in the google box type in "99 fuel pump test terminal




If you apply 12v to that the pump should run and you can test FP and leakdown.

 

Sorry for the delay in response.....we been getting hit with rain like crazy in North Carolina. Just got back on it today....pulled tank back out and run 12v on the pump and everything was fine with pump. Run a jumper wire to the fuel pump test terminal and nothing, checked relay terminal and only getting power on the 30 pin or top right pin. Looking at the wiring diagram in the manual leaves me to only guess the PCM may be the problem. With the new relay, oil switch, fuel pump and checking all fuses still getting no power on the gray wire at the pump. At a Loss here still.

 

I had a similar issue and it turned out to be the ignition switch.

 

@Blazinat40 Were you ever able to find the fix to your problem? If so, what was it? I am having the same issues as you.

 

You systematically test until you find the fault.

What problem are you having? Crank but no start? How do you know its the fuel pump, have you tested fuel pressure?

First is to do the fuel pressure test in the sticky. If no pressure then we test the electric path. First is the path from the ECM to energize the FP relay and then if OK, the power path through the relay contacts to the pump, then voltage and ground at the pump.

Let me know if you need any guidance for testing. Keep in mind that at key on the fuel pump is only energized for a few seconds until you start the truck.


George

 

Most likely this is a problem with the wiring. I had something similar to my Dodge 1500, after replacing the fuel system, problems started, it turned out there was a poor-quality fuel pump and filter. Here https://davesoilchange.com/filter-for-6-7-cummins/ I found Best Fuel Filter For 6.7 Cummins best filter option for my car.

 

let me know if I can help in anyway

George