Fuel Pump issue - help

[Ourobos]

OK, so I have an 86 LX, I have put ALL wiring from an 86 5.0 SEFI into it (mine was a 2.3). I am trying to make sure my fuel system works before I bolt the tank up. I currently don't have an inertia switch, as the 86 2.3 cars didn't have them, and I have those two wires jumpered together FOR NOW, I will get a switch. I put power directly to the fuel pump and it kicks on, so that is good (new pump, it better be). When I turn the key ON, I hear the ECU relay clicking, but can't really hear the FP relay, but when I turn the key off, I hear the FP relay click. Maybe it works that way? Anyways, the fuel pump WON'T kick on to prime or anything. Dunno if the FP relay is getting proper voltages, or what else my problem could be. I have tried two fuel tank wiring harnesses also. At the FP relay wiring under the seat, with the key off, I am getting :

Yellow - 12v
1st Pink / Black - nothing
2nd Pink / Black - .3v
Green / Yellow - nothing

With the key in RUN :

Yellow - 12v
1st Pink / Black - nothing
2nd Pink / Black - 12v
Green / Yellow - .3v

So the 2nd Pink/Black and the Green/Yellow change with the key.. Any of this look right or have any ideas? Would like to get this 418 fired up.


Thanks

[Ourobos]

My relay is labeled 1-5.. (or is it 10-50)

Color | Ign. Off | Ign. On (Relay out) | Ign. On (Relay in) Relay Post #

Yellow | 12v | 12v | 12v | 4
Tan / Green | 0v | 0.3v | 5.5v | 1
Red (pk)/ Blk |0v | 0.3v | 12v | 2
Pink / Blk | 0v | 0v | 0v | 3

One I had listed as Pink/Black might actually be red, hard to tell. But the one that is MORE pink, is always 0v, position #3 on the relay. Ideas?

[TWR2003]

Look at this TMoss diagram for the 86 EEC:

http://www.veryuseful.com/mustang/te...ng-ECC-EFI.gif

The FP relay is on the left hand side of the diagram just above the EEC. The wires at the FP relay are:

YEL - one side of power contacts - 12V at all times (from Bat+)
PNK/BLK - other side of power contacts - output to FP (hot when relay is energized)
RED/BLK - one side of relay energizing coil - 12V from EEC relay (12V when key is on)
TAN/LGRN - other side of relay energizing coil - ground at EEC pin 22

Two things have to happen for the FP to run:
1. Power must be supplied to one side of the FP relay energizing coil via the EEC power relay. This relay is turned on when the key is turned to on.
2. The other side of the FP relay energizing coil is grounded by the EEC via pin 22. The EEC supplies a ground to pin 22 when it receives a 'key on' signal via 12v supplied to pin 37. With the EEC energized (via the EEC power relay) if the EEC does NOT detect a signal from the PIP sensor (inside the distributor) the ground is removed after 1-2 seconds. That is why turning the key to 'on' but not cranking the engine will cause the 1-2 second fuel pump 'prime'. If the EEC detects a signal from the pip sensor - which produces a sine wave signal any time the distributor is rotating (ie during crank or run) the EEC will continue to provide a ground to pin 22 and the FP relay contacts will remain closed and the FP will continue to run.

The voltages you are seeing in the tests you did seem to be fine for key off and key on but you need to check for ground at TAN/LGRN (EEC pin 22) - that is the key. Disconnect the FP relay and check for continuity between the TAN/LGRN and chassis ground both in key off and key on. If your EEC is working correctly:

Key off, TAN/LGRN = no continuity to ground
Key on, TAN/LGRN = continuity to ground for 1-2 seconds

Look into this and let me know

T

[Ourobos]

Thanks.. Turns out my brand new FP relay was bad it seems.. I pulled the other new A/C WOT relay and plugged it in under the seat, and the pump primed.. Do I 'NEED' the A/C WOT relay if I'm not running A/C, does it power anything else? Reason I ask is I had converted a 3.8 CFI car to 5.0 SEFI before, and I think I remember it wouldn't run without it.. Could have been a bug.. Also, any good sources for GOOD relays for the FP? These parts store ones are apparently junk, and don't want to be stranded due to it.

Thanks

[Ourobos]

Also.. Another issue I have noticed so far (sure there will be more).. When I click either turn signal, left or right, the wiper motor comes on.. Anyone have any ideas on that, bad multifunction perhaps?

[Ourobos]

Still have a few issues. I swapped out both switches on the column, the wipers come on when I turn either turn signal on. Otherwise they work fine, except no delay wipers work, low and high do work.. Ideas?

ALSO, back to my original issue, I got all the fuel system hooked up, fuel in the tank, turned the key on, and the pump comes on and primes the line to 40 psi at the regulator, but it DOESN'T go off.. Fuel pump stays on... Ideas on that?

[TWR2003]

Do I 'NEED' the A/C WOT relay if I'm not running A/C, does it power anything else? Reason I ask is I had converted a 3.8 CFI car to 5.0 SEFI before, and I think I remember it wouldn't run without it.. Could have been a bug.. Also, any good sources for GOOD relays for the FP? These parts store ones are apparently junk, and don't want to be stranded due to it.

Thanks

The EEC-IV does NOT need the WOT relay installed to operate. The WOT relay works basically like the FP relay in that the ground signal for the relay's energizing coil is provided by the EEC - in this case via EEC pin 10. The only thing the WOT relay controls is the AC compressor clutch (with the AC on it turns OFF the clutch at WOT).

You can still get Motorcraft Ford relays:
http://www.latemodelrestoration.com/...uel-Pump-Relay

I dont use any other brand.

[Ourobos]

Any ideas why my fuel pump won't turn off, or how to diagnose? How about the turn signals turning on the wiper motor?

[TWR2003]

Any ideas why my fuel pump won't turn off, or how to diagnose?

I already gave you that info:

The voltages you are seeing in the tests you did seem to be fine for key off and key on but you need to check for ground at TAN/LGRN (EEC pin 22) - that is the key. Disconnect the FP relay and check for continuity between the TAN/LGRN and chassis ground both in key off and key on. If your EEC is working correctly:

Key off, TAN/LGRN = no continuity to ground
Key on, TAN/LGRN = continuity to ground for 1-2 seconds

Look into this and let me know

T

[Ourobos]

Sorry, must have read past that..

I pulled the FP relay, and with my test light grounded, I got nothing on the Tan/LGrn with the key off, and nothing with the key on. Does that mean the ECU isn't sending a cut off signal from pin 22 to the FP relay? Bad ECU?

[TWR2003]

Sorry, must have read past that..

I pulled the FP relay, and with my test light grounded, I got nothing on the Tan/LGrn with the key off, and nothing with the key on. Does that mean the ECU isn't sending a cut off signal from pin 22 to the FP relay? Bad ECU?

You are not testing correctly. The EEC supplies GROUND not +12V. You need to check for GROUND at TAN/LGRN (EEC pin 22).

-->Leave the FP relay removed. Connect one side of your test light to +12V power (you can get it right at the YEL at the FP relay) and connect the other side to TAN/LGRN (EEC pin 22).

Key off = no light
Key on (engine off) = test light lights for 1-2 seconds then goes off. Each time you turn the key off then back on the test light should light for 1-2 sec then turn off.

Check that and let me know.

T

[Ourobos]

Thanks for the clarification, electrician I am not..

With my alligator clip on the yellow constant, and probe on the Tan/LGrn, the light comes on with the key off.. It's on with the key on also. So is my #22 wire grounding out somewhere? Should I check it at pin #22 at the other end, ECU disconnected? Or does this tell you something else?

Thanks again

[TWR2003]

Thanks for the clarification, electrician I am not..

With my alligator clip on the yellow constant, and probe on the Tan/LGrn, the light comes on with the key off.. It's on with the key on also. So is my #22 wire grounding out somewhere? Should I check it at pin #22 at the other end, ECU disconnected? Or does this tell you something else?

Thanks again

Disconnect the EEC from the 60 pin connector and see if the TAN/LGRN at the FP relay is still connected to GROUND. If it is then you have a short to ground somewhere in that wire. If it is not then you have a problem with the EEC. Do you have access to a spare EEC you can try? It doesnt have to be from an 86, any 86-88 SD EEC will work.

Let me know
T

[Ourobos]

Thanks T, I removed the ECU, and with my alligator clip still on the yellow constant, I probed slot #22 on the harness and got no light key off or key on.. Guessing bad ECU. I have another hopefully on the way today to verify. Will update.

[TWR2003]

Thanks T, I removed the ECU, and with my alligator clip still on the yellow constant, I probed slot #22 on the harness and got no light key off or key on.. Guessing bad ECU. I have another hopefully on the way today to verify. Will update.

OK,

If you cannot borrow a known good EEC - before you spend coin on a new EEC you should verify that the EEC is recieving power. As counter-intuitive as it may seem the EEC must recieve power and be 'on' to supply the FP relay ground at pin 22. The EEC gets its power via the EEC power relay. The EEC power relay is shown in the left side of the diagram below the EEC:

http://www.veryuseful.com/mustang/te...ng-ECC-EFI.gif

BLK/ORG - one side of power contacts - 12V at all times (from Bat+)
RED - other side of power contacts - output to EEC pin 37 and FP relay via inertia sw (hot when relay is energized)
RED/LGRN - one side of relay energizing coil - 12V from ignition sw (12V when key is on)
BLK/LGRN - other side of relay energizing coil - ground at EEC pins 40/60

When the key (ignition sw) is turned on the EEC relay should energize and the EEC recieves power at pin 37. When this happens the EEC should be turned on and a 1-2 second ground signal should be seen at pin 22 (as dicussed earlier). With the EEC disconnected from the 60 pin connector verify that you have 12V at pin 37 with the key on (the EEC relay should click on).

Also, since you have the EEC disconnected from the harness please do one more test to verify the operation of the FP circuit less the EEC:

1. Re-install the FP relay.
2. Connect a jumper wire between pin 22 on the EEC 60 pin connector and ground.

Key off = pump off
key on = pump on (FP relay clicks on)

With the key on and one end of the jumper installed in pin 22 ground/un-grounding the other side of the jumper should make the FP/FP relay come on (ground) and go off (un-ground).

Essentially what Im having you do here with these tests is to try to establish by process of elimination is that the only possible cause of the problem is the EEC (ie not in the harness or relays).

Let me know.
T

[Ourobos]

I've always heard the ECU relay clicking, but did your test to see if it tells you anything :

My voltages at the ECU relay were exactly what you stated they should be above.

With the FP relay reinstalled, I jumpered the TAN/LGreen wire there to the frame, ECU still disconnected. Key off, no fuel pump. Key on, fuel pump on constantly. Looking like a ECU?

[Ourobos]

Just put a new A9L in, and the fuel pump primes up and turns off as it should, thanks for the education on continuity.

I do have another issue, possibly more as I move along. All the wiring in this car came from a 86 5.0 EFI car except the dash harness was from an 85 GT. Right now, if you turn the turn signals on either way, the wiper motor comes on. I'm wondering if the 85 dash harness was different, or if you had any other ideas. I tried some new levers, both the wiper and turn levers, and it's the same thing. Any testing I can do you can help with (or anyone else)?

Thanks again.

[Ourobos]

And a more pressing issue.. I got the 418 fired up with the fuel system working, but had to do it via the solenoid.. I DID have it turning by the key, but it only turned 4-5 revolutions and stopped working. I have the wires in the tranny tunnel jumped (it was like that when it turned with the key). Any ideas on tracing that down?

[TWR2003]

Just put a new A9L in, and the fuel pump primes up and turns off as it should, thanks for the education on continuity.

I do have another issue, possibly more as I move along. All the wiring in this car came from a 86 5.0 EFI car except the dash harness was from an 85 GT. Right now, if you turn the turn signals on either way, the wiper motor comes on. I'm wondering if the 85 dash harness was different, or if you had any other ideas. I tried some new levers, both the wiper and turn levers, and it's the same thing. Any testing I can do you can help with (or anyone else)?

Thanks again.

It is very possible that the 85 and 86 underdash harness were different.

[Ourobos]

Any ideas on tracing down the start wire to the solenoid?

Here's a quick video of me setting the timing :

[TWR2003]

And a more pressing issue.. I got the 418 fired up with the fuel system working, but had to do it via the solenoid.. I DID have it turning by the key, but it only turned 4-5 revolutions and stopped working. I have the wires in the tranny tunnel jumped (it was like that when it turned with the key). Any ideas on tracing that down?

What did you do at the solenoid to get it to crank?

Testing the starter relay and circuit:

1. Remove the small RED/LBLU wire from the starter solenoid. Connect your test light between the end on the RED/LBLU and ground. Key on = test light should light. If not there is a problem with that wire or the ignition switch (where it originates).

2. Connect a jumper wire to +12V (Bat +). Touch the other side of the jumper to the small terminal on the starter solenoid that you removed the RED/LBLU wire from. The starter motor should crank the engine. If not the solenoid is failed.

Let me know.

T

[Ourobos]

2. - That is how I am able to start it, turn the key on, and jumper the solenoid from the Start post to the positive post on the relay..

1. With the test light in the red/blue start wire, and the alligator clip on ground, I get no light, key off or on or in START.

Any other ideas where to probe out to find my problem. It's strange that it cranked for 4-5 revolutions the other day, then just stopped.

[TWR2003]

2. - That is how I am able to start it, turn the key on, and jumper the solenoid from the Start post to the positive post on the relay..

1. With the test light in the red/blue start wire, and the alligator clip on ground, I get no light, key off or on or in START.

Any other ideas where to probe out to find my problem. It's strange that it cranked for 4-5 revolutions the other day, then just stopped.

It appears that you are not getting 12V thru the ignition switch to the starter solenoid start terminal. I would suspect a problem at the ignition switch however since you also seem to have issues related to your mixed harness arrangement it could also be due to that.

Looking at this same schematic again:
http://www.veryuseful.com/mustang/te...ng-ECC-EFI.gif
The ignition switch and wiring to the starter solenoid (called starter 'relay' in the diagram) is show in the upper left hand side of the diagram.

And also this one:
http://www.veryuseful.com/mustang/te...itchWiring.gif

1. You will need to disconnect the steering column harness connector from the ignition switch and check for continuity from the WHT/PNK at the ignition switch connector to the RED/LBLU at the small connector at the starter solenoid.

2. You also need the check the continuity of the ignition switch itself. You need to verify continuity between the terminals that had the large YEL wires and the terminal that had the WHT/PNK wire when the switch is held in the START position.

Let me know
T

[Ourobos]

Could be a few things, LMK what you think.

Put the test light in the Red/Blue at the solenoid, probed the white/pink of the ignition wiring while disconnected, and got nothing. Tried to turn the key to START with the clutch in also, still nothing.

AND with the clip on the position of the Yellow wire in the ignition switch and the probe on the White/Pink terminal.. Still got nothing. Even with the clutch in and turning the key to RUN.

Bad ignition and wiring?

And about the 86/85 dash harness wiring, from everything I've read and comparing them side by side, they look identical, wiring colors and all.


LMK what you think or ideas on what to do next.

Thanks

[TWR2003]

Could be a few things, LMK what you think.

Put the test light in the Red/Blue at the solenoid, probed the white/pink of the ignition wiring while disconnected, and got nothing. Tried to turn the key to START with the clutch in also, still nothing.

AND with the clip on the position of the Yellow wire in the ignition switch and the probe on the White/Pink terminal.. Still got nothing. Even with the clutch in and turning the key to RUN.

Bad ignition and wiring?

And about the 86/85 dash harness wiring, from everything I've read and comparing them side by side, they look identical, wiring colors and all.


LMK what you think or ideas on what to do next.

Thanks

1. You will need to disconnect the steering column harness connector from the ignition switch and check for continuity from the WHT/PNK at the ignition switch connector to the RED/LBLU at the small connector at the starter solenoid.

2. You also need the check the continuity of the ignition switch itself. You need to verify continuity between the terminals that had the large YEL wires and the terminal that had the WHT/PNK wire when the switch is held in the START position.

Let me know
T

OK, you cant test that way for continuity. Follow below to do the above tests using your test light - you will also need a single jumper wire:

1. Disconnect the ignition switch connector and the small RED/LBLU connector at the starter solenoid. Connect one lead of your jumper wire to +12V (the YEL contact on the ignition switch connector will do) and the other side to the WHT/PNK contact on the connector. Connect one side of your test light to the small RED/BLU connector at the solenoid and ground the other side. If the circuit between the WHT/PNK at the ignition switch connector and RED/LBLU connector at the solenoid is good the lamp will light.

2. With the ignition switch connector still off the switch connect one lead of your jumper wire to +12V (the YEL contact on the ignition switch connector will do) and the other side to the YEL contact on the switch. Connect one side of your test light to the WHT/PNK contact on the ignition switch and ground the other side. If the switch contacts between the YEL on the ignition switch and WHT/PNK on the ignition switch are good the lamp will light when the key is turned to start.

And about the 86/85 dash harness wiring, from everything I've read and comparing them side by side, they look identical, wiring colors and all.

Thanks

The fact that you have the turn signal switch operating the wipers, etc, tells me something is NOT connected correctly. You need to recognize that some different years harnesses where very similar but not exactly the same. Ford would use the same basic molded connector shells over several years for the same function but upon very close scutiny you will find that the exact wire colors in a given position in the connector was different. I would look very closely at the connectors where the 85 underdash harness plugs into the 86 column harness and underdash harness. Follow across the connector halves and be certain that all mating contacts on both sides of the connectors have the same color code.

Let me know
T