another makg or allen d question

baddis · Dec 28, 2007

the truck is an 88 ranger with a 2.9 auto. i was driving along today and the truck just died. i checked for spark and it does have it. pulled the cap off of the schrader valve on the fuel rail and there was a little pressure but not a lot. is there a way to tell what fuel pump has died? the in line or in tank?

holyford86 · Dec 29, 2007

it seems that you have already verified that the fuel pumps are running. I would test the fuel pressure and see what you get. if the high pressure pump is bad the in tank pump will not be able to push the pressure that the frame rail pump can. The frame rail pump may be able to draw fuel out of the tank for a little while but it will eventually burn up from the added strain. I would try running power direct to each of the pumps from a battery and see if they run. I lost a ground on my frame rail pump that caused my truck to do what you describe.

baddis · Dec 29, 2007

ok i had time to look at it today and i have no power to the pumps. i can hear the relay clicking but no power to the pumps. where do i start?

IMenriched · Dec 29, 2007

baddis said:
ok i had time to look at it today and i have no power to the pumps. i can hear the relay clicking but no power to the pumps. where do i start?

Are your certain that fuel pump relay is working? There are 2 other in the same area.
I recently replaced mine(fuel pump relay), I also could here clicking...apprently it was the other relays...plugged in the new one and it was running again. relative cheep & real easy to change. Seems like your on the right track rule out the easy/simple stuff.

baddis · Dec 29, 2007

i felt the relay as someone turned the key. there are 2 relays clicking. one i assume is the fuel pump and the other is a/c relay i think.

Mutant Pony · Dec 29, 2007

The two relay next to each other are the (1) fuel pump and (2) eca relays. The ECA relay has to turn on or the FP relay won't. Even if both relays turn on, The wires on the bottom of the relays corrode in two(check there), If the inertia switch doesn't work the fuel pumps won't run. If the fuel pumps have lost ground they won't run. If the connectors at the fuel pumps are corroded the pumps won't run. If you happened to get some water in your fuel system and it froze the pumps won't run.
The biggest question is: Have you replaced your filter lately?

greaseyfingers · Dec 29, 2007

Mutant Pony said:
The two relay next to each other are the (1) fuel pump and (2) eca relays. The ECA relay has to turn on or the FP relay won't. Even if both relays turn on, The wires on the bottom of the relays corrode in two(check there), If the inertia switch doesn't work the fuel pumps won't run. If the fuel pumps have lost ground they won't run. If the connectors at the fuel pumps are corroded the pumps won't run. If you happened to get some water in your fuel system and it froze the pumps won't run.
The biggest question is: Have you replaced your filter lately?

you mentioned a ECA relay... what does the abbreviation ECA stand for...

does each fuel pump have it's own relay... or, does one relay power both fuel pumps...

if each fuel pump has it's own relay, what color relay is for each fuel pump, as I would like to know, when I check mine...

Psychopete · Dec 30, 2007

Could be a bad fuse link. Check for power before and after the relay. Misplaced my EVTM, not sure what the wiring is on the relay. I am not even sure if it showed it either..

Green is fuel pumps, brown is for the engine's computer. Switch side of the fuel pump relay is from the computer, which is why they won't turn on if the computer doesn't. Wiring diagram would be of some help.

I know mine was green because I had my timing 180 off and the cylinders flooded a little. I unhooked the green relay and turned over the engine to hear a a little popping, the unburnt fuel in the cylinders was burning, so it was apparent that the computer and sensors were still getting powered.

Pete

baddis · Jan 2, 2008

update.... ok i have checked the wiring and from my truck to the book the colors do not match. i have no power at the fuel pump relay or the inertia switch. but i do have power at pin 1 at the computer.but it looks like i should have power at pin 8 also. and i do not. i checked for power at the eec relay and i have power there but the relay got warm to the touch. is this normal? meaning it is at 0 outside and maybe 40 inside and it got warm enough that you could tell it was warm.

shadetree · Jan 3, 2008

You will not have power to the inertia switch or pumps if the engine is not running. When the ignition switch is first turned on, you should have power for a couple of seconds to prime the fuel system. You should be able to hear the pumps running for this short period of time. The computer then shuts off the pumps waiting for ignition pulses from the distributor.

If you can locate the self test connector you can keep power to the pumps for diagnosis. The connector is on the pass side of the truck between the fender and the firewall. It looks like an unplugged electrical connector in the shape of a house when looking at the front of the connector. The top slopes on each side, and it has six slots for connections, two on top and four on the bottom.

To keep power to the pump, of the four slots on the bottom of the connector, run a ground wire from the slot on the lower right of the connector to a good ground. I use the battery ground.

This grounds the coil side of the fuel pump relay keeping the contacts closed, and power going to the pumps.

Fuel pump relay:
Red wire = power to the relay coil from the EEC relay.

Tan/lt grn wire = relay coil ground going to pin 22 of the computer and the self test connector. This is the point you ground to the battery negative.

Yellow = power from the fuse link on the fender starter relay. This is where the pumps get running power. It is one side of the contacts inside the fuel pump relay. If the fuse link is open, no power.

Orange/lt blu = power out of the fuel pump relay to the inertia switch.

EEC relay:

This relay supplies power to the computer, and sensors, and fuel pump relay.

Yellow = power from another fuse link on the fender starter relay. This is main power to the EEC relay contacts

Red = Power out of the EEC relay contacts to the fuel pump relay and sensors.

Red/lt grn = power from the ignition switch

Blk/lt grn = ground side of the EEC relay coil going to the computer.

The fuse links are like fuses. If they have opened up, no power. shady

greaseyfingers · Jan 3, 2008

shadetree said:
You will not have power to the inertia switch or pumps if the engine is not running. When the ignition switch is first turned on, you should have power for a couple of seconds to prime the fuel system. You should be able to hear the pumps running for this short period of time. The computer then shuts off the pumps waiting for ignition pulses from the distributor.

If you can locate the self test connector you can keep power to the pumps for diagnosis. The connector is on the pass side of the truck between the fender and the firewall. It looks like an unplugged electrical connector in the shape of a house when looking at the front of the connector. The top slopes on each side, and it has six slots for connections, two on top and four on the bottom.

To keep power to the pump, of the four slots on the bottom of the connector, run a ground wire from the slot on the lower right of the connector to a good ground. I use the battery ground.

This grounds the coil side of the fuel pump relay keeping the contacts closed, and power going to the pumps.

Fuel pump relay:
Red wire = power to the relay coil from the EEC relay.

Tan/lt grn wire = relay coil ground going to pin 22 of the computer and the self test connector. This is the point you ground to the battery negative.

Yellow = power from the fuse link on the fender starter relay. This is where the pumps get running power. It is one side of the contacts inside the fuel pump relay. If the fuse link is open, no power.

Orange/lt blu = power out of the fuel pump relay to the inertia switch.

EEC relay:

This relay supplies power to the computer, and sensors, and fuel pump relay.

Yellow = power from another fuse link on the fender starter relay. This is main power to the EEC relay contacts

Red = Power out of the EEC relay contacts to the fuel pump relay and sensors.

Red/lt grn = power from the ignition switch

Blk/lt grn = ground side of the EEC relay coil going to the computer.

The fuse links are like fuses. If they have opened up, no power. shady

I, recently, changed my starter's solenoid switch and was wondering about the three wires, that are attached to the starter's solenoid hot terminal lead, from the battery's positive post...

I thought they were, probably, some kind of fuse links... but, I wasn't sure what they were for, exactly...

I thought they might be for the fuel pumps... however, I wasn't sure...

does each pump have it's own fuse link ?? or, does one fuse link power both pumps ??

if one fuse link powers both fuel pumps... what do the other two fuse links power ??

I can hear my front fuel pump when it runs, located along the frame rail... but, when the front pump is runnning, I can't tell if my fuel pump, inside the fuel tank, is running, cause of the noise that the front fuel pump is making...

what's the best way to find out, or hear if my rear fuel pump is running... can I dissconect the power to front fuel pump, and send power, only, to the rear fuel pump, to find out...

you seem pretty knowledgable how a ranger's fuel injection system works, regarding the operation of their fuel pumps...

so, I thought I'd ask your advice... as, I'd like to find out, for sure, if my rear fuel pump is working, properly, as it's suppose to...

holyford86 · Jan 4, 2008

you could disconnect the high pressure pump to test for operation of the low pressure pump but don't do it for long or you could burn the pump up.

greaseyfingers · Jan 4, 2008

holyford86 said:
you could disconnect the high pressure pump to test for operation of the low pressure pump but don't do it for long or you could burn the pump up.

where's the easiest place to disconnect the frame rail's high pressure fuel pump's electrical energy source, when I try to hear, if the fuel pump is running that is inside of my fuel tank...

does each pump have it's own seperate relay and it's own seperate fuse link attached to the engine starter's relay, as it's power source...

when you run the fuel tank pump, by itself... should I easily be able to hear it, when it's running... does it help, to take of the gas cap to hear any sound coming from inside the fuel tank, when trying to find out, if the pump is making any sound, when it's suppose to be running, as I test it...

holyford86 · Jan 5, 2008

right near the pump there should be a connector to unplug it. Both pumps are powered by a common power source and a common relay, meaning they connect to the same fusible link.

baddis · Jan 5, 2008

update #2 thanks to shady i have gotten the frame rail pump working. i run a jumper wire from the relay to the hot side of the pump. hit the key and wirrrr. pump running. now i am going to try the same thing with the in tank pump. what is the color for the wire on the hot side of the tank pump? my book only shows one pump. and thanks again shady, you have been a big help so far.

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