Wiring issue EFI

[Dawg_enD]

Hello!

I have an Explorer 5.0 + 4R70W in my Bronco. Recently, it quit starting. I was able to get it started a couple times by randomly jiggling wires under the dash, but I haven't wanted to trust it since then. I'm trying to get an idea of where to aim before I just start trying to tear into it, especially since it's currently stuck in my garage with 1/2 open driver's door access only, and a motorcycle lift under it. =)

Here's what I know:
In the engine compartment are two solenoids. One is for the starter, I don't know what the other one does. Both *appear* to be working fine, with power going out when the key is on, but not when the key is off.
I do not hear the in tank fuel pump whine when I turn the key on now.
It was wired to have a light inside provide the resistance the system needs to start up when the key is turned on, no lights come on when I turn the key on. (I'm a little fuzzy on the details there, it's been a while)
The chassis has been rewired, the EFI harness is an EFI guy harness that I had installed for me by a reputable shop. (am I allowed to post their name here? They were great)

Oh. One final thing. Most of the gauges don't work, though they haven't for a couple years. The hazard lights blow a fuse, so I haven't used them in a few years. Those were going to be my summer projects, but none of that stuff matters if I can't get it to run.

Guys, I haven't done much work on the Bronco in awhile, so you may have to dumb things down a bit for me. Messy divorce, sole custody of my girls, 3 jobs etc... working on it just hasn't been that important. However, they love riding in it with the top off during the summer, probably as much as I do. I'd love to get it back on the road, so any tips / direction you can provide would be very appreciated.

Thanks all!
-Mike

 

[DirtDonk]

Hey Mike. Sorry to hear you’re having these kinds of troubles.
But it does sound like you’ve got some cascading effects going on. You’ve had electrical problems for quite a while. Now you have more.
Do you know what brand chassis harness was used during the rewire? Or was it Custom?
And yes, you can post names up because that usually helps everybody whether it’s a good or bad review.

It sounds like you have some serious motivation in the form of three young ladies that want to go for a ride!
Sorry I don’t have an answer at the moment off the top of my head, but good luck.
And please post more information as you think of it. Any pictures you feel like posting as well.

 

[Dawg_enD]

Hiya DD, you caught me right before going to bed.

I bought the harness off an inmate about 15 years ago now. It was a Centech, I believe. I did the chassis rewire myself, I used Weatherpacks / etc. All 4 Fun Offroad in Albany, Oregon got the EFI install across the goal line for me a few years ago.


****I should mention... All I asked All 4 Fun to do was get me on the road, as the previous mechanic (who had it for close to a decade) had left me hanging. All 4 Fun was great, so don't anyone get the impression that they left the job unfinished.... they left it right where I wanted it, on the road and in a position for me to finish the job. I have NOTHING but good things to say about their service or work, which was phenomenal.***

Bed time!!!

 

[pcf_mark]

May be too late now but I did my EFI wiring in such a way it is completely isolated from the truck w/ the exception of the key on signal. That signal closes a relay that powers up the fuel pump, EFI controller and ignition circuit. If the truck goes dead I can always just hot wire 12v to the relay and I am running. I just did not trust much of the 50 yr old wiring.

All that being said if you do not hear the fuel pump start down that path first. Is it getting power and has a ground? if not you can bypass the source and put 12v to it then see if the truck runs. If not you know you have more work on the pump side. If it does not run then feel the injectors and see if they are ticking when you crank to see if the ECM is alive and sending signals. If they are not the ECM is not getting power so follow down that path - wiring, fuse, key switch. Figuring out which branch can really narrow it down.

 

[EFI Guy]

Grab a test light and give me a ring! 720-58TUNEZ.

 

[Dawg_enD]

Thanks, Gary. Yet another Bronco vendor who is awesome, and has been a big part of getting my Bronco on the road!

 

[Dawg_enD]

Think I got it figured out, with Gary's help. Thank you to all who posted!

 

[904Bronco]

Think I got it figured out, with Gary's help. Thank you to all who posted!

Please post up what you have found... adds info for the next person who has issues.

 

[Dawg_enD]

I don't think it will help anyone else much, but here you go:

1. A brake warning wire was unplugged from the ignition.
2. Another wire (brake switch also, maybe) looks severed.
3. A splice has one wire that appears to be coming loose from the original wire.
4. The wiper power from the Centech harness isn't plugged into anything. This is odd, because the wipers get power. They don't, however, park. This may be part of the problem.

Fuel gauge is still not working, but I've isolated that to the gauge itself, I believe. But it fires up and runs just fine right now, which is the important part.

-Mike