87 ranger, 2.9 v6 Fuel pump help

[eternalphoenix64]

So I bought this truck back in November. Almost immediately developed a stutter. Previous owner admitted it existed, but thought he got rid of it with new fuel filter, got it for a steal so I wasn't upset.

Anyways, in process of deciding which route to try fixing first, took it out and would stutter horribly if I tried to give it gas. Decided to get a tow instead of idle it home. At this point, I had gotten new plugs/wires/cap/rotor/coil/TFI and PCV valve. Put it all in and went to fire it up and suddenly my in line fuel pump won't work. I don't hear it when I turn keys on.

So I replaced the pump last weekend and it still won't work.

Other (possibly unrelated) symptoms:
Broke one of bolts securing TFI
Battery getting weak
A couple relays (I believe fuel pump and ECM) had badly corroded pins and had cracked casings, so I replaced those too.
There is a good deal of "Bubba dun..." work on this truck. Including removed TPS and O2 sensor, and a cut parking brake cable.

Other immediate future plans involve replacing in-tank fuel pump, fuel filter after that, valve cover gaskets, and upper and lower hoses. Possibly a couple other things.


Any help is greatly appreciated. I bought this truck as a running project for me to have some fun in the back woods and now it's just sitting in the street.

 

[wildbill23c]

So does it start at all? Does it just idle and not accelerate?

I have an 88 Bronco 2 that suddenly wouldn't start and traced it to a bad fuel pump shut off switch also called an inertia switch, hit a little bump and it would trip the switch rendering the vehicle unusable.

There should be a fuel pump relay as well, if that relay is bad you won't get the electric fuel pump to run.

So check the fuel pump relay and the inertia switch. You can in theory bypass the inertia switch...at least temporarily, not sure I'd make it permanent but for testing purposes you could just bypass the switch and see if it runs properly that way.

 

[alwaysFlOoReD]

Get a fuel pressure gauge and hook it to the schrader valve [looks like a tire valve], I believe on the passenger side of the intake. You should see ~ 40 psi. If not then there is a pump problem, and if you replaced the frame high pressure pump then the in tank low pressure pump is probably the problem.

 

[eternalphoenix64]

I had been wondering about the inertia switch, a little. I don't find it very likely because the pump would run before I did the tune-up.

To clarify, I replaced the high pressure pump because it would not turn on when I turn the keys on. You can normally hear it 4 a second or two if you turn the key on but not try to turn the truck over. After replacing the fuel pump and the fuel pump relay, it still won't come on. I have also verified that I did hook it back up. I am planning to do some tests this weekend to determine whether or not it is getting power.

 

[eternalphoenix64]

Quick update: one of the previous owners has already bypassed the inertia switch, and the fuel pump isn't getting any voltage.

Any updated thoughts?

 

[Psychopete]

There's a fuel pump test on the diagnostic connector, ground it and see if the pumps will run when key is on. It connects pin #22 in the diagram below to ground and overrides computer control.

If they run, the fuel pump circuit is OK (fuse link, relay, etc).

If they don't turn on with the test grounded, though the wiring colors might differ, this is the flow of the circuit: