86 ranger 2.9 no power to frame rail fuel pump

[jovibuilt]

I am not getting any power to the fuel pump on the rail.I replaced the pump relay and I am getting power to the relay,but no power to the pump.I checked the connector under the master cylinder and no power.Any one have any ideals?I am not used to working on 2.9s.Most of mine are 4.0's.I need to get the truck home.Thanks

 

[adsm08]

Ok, new relay, power into the relay (on which side?), no power to the split connector.




If you've gotten this far I assume you know how to read a relay diagram.

Does the coil side get power and ground?

Does the gate side have power?

Get a spare headlight and hook it up to the coil side connections of the relay's connector. See if it lights up when you flip the key on.

 

[jovibuilt]

I used this found it on here.
(The fuel pump relay has five wires.
yellow:from the fusible link at the starter relay.Always live.
red:from the eec relay.
tan-lt green:from the ecu.
orange-lt blue x2 :to the inertia switch and the ecu.)
The red and yellow have power.Going to go try the headlight trick now.

 

[adsm08]

The headlight trick is something I picked up from my shop foreman. Back a few years ago that was how Ford wanted you to load test a circuit. Hook up a headlight to it in place of the designed load and turn it on.

The light doesn't pull enough current to fry anything but needs enough voltage that if it lights, the circuit is good.

 

[jovibuilt]

ok hook it to the out going side of the rely plug?Do you know where to get a fuel pump relay diagram for the 86?I could only find one for an 89.
http://www.therangerstation.com/forums/showthread.php?p=1057953#post1057953

 

[adsm08]

Looking at this, I want you to hook the light into the red and the tan/light green wires, flip the key on, and see if the light lights up for a few seconds.

 

[jovibuilt]

no tan and green wire.I took pictures left to right is front to back the one on the right should be fuel pump right?

Middle relay (green one) wire colors

Left relay (black one) wire colors

Now the in tank pump is one getting a little voltage not enough for it to run but to make a test light pulse.And Ideals?

 

[adsm08]

From left to right those are

PCM power, Fuel pump, and A/C/ WOT cutout. Fuel is green.

 

[jovibuilt]

the brown (the right one) one wire colors

 

[jovibuilt]

Well I know its good (green one) tried it on my broncoII and had power to the rail pump?

 

[adsm08]

You have a B2 that runs? If so, swap computers and see if the ranger fires up.

 

[jovibuilt]

You have a B2 that runs? If so, swap computers and see if the ranger fires up.

Swapped them still the same.No power to the rail pump and only a faint pulse to the tank pump not enough to run it?I am lost.

 

[adsm08]

Ok, computer is not the issue.

Have you verified power to and from the green center relay?

 

[jovibuilt]

computer was bad and the plug for the inertia switch was bad too.It runs

 

[adsm08]

Cool.