86 B2 Fuel Pump Relay

[The Slider]

My 86 Bronco II has been sitting for a while and lately since I got the Transmission rebuilt everything was fine until the past couple of days. The other day I went to start it and it just cranked, I realized I didn't hear the fuel pump relay. I played with the relay and it came on. So i assumed the relay was sticking. drove fine for the next few days, I got the NEW relay and installed it and NOTHING!!! So I played with the wires and jiggled them around and it came on!!! I can NOT find out WHERE that wire is that's loose! Do anyone know what wire it POSSIBLY could be? My other 1/2 wants to get rid of it because all the problems we have had, but it is CLEAN and it has been in the family since day ONE and I DO NOT want to get rid of it!

Thanks!
Chaz.

 

[The Slider]

Wow!!! I was hoping someone might know what harness to check or is this might be a common thing. Guess not

 

[wildbill23c]

If you are playing with the wires and it suddenly causes the relay to work, then obviously you should be able to move each wire around until you get results then know which wire to repair.

On the other hand maybe its not the wire itself but the terminated connector in the relay socket, or the socket itself is corroded causing a bad connection and moving wires around moves the connectors in the socket around enough to restore the connection until the next bump you hit in the road and it knocks the relay out of position again.

I'd make sure the connections are clean, even add some dielectric grease if needed to protect from corrosion.

Obviously you replaced the relay and that didn't remedy the problem so you've traced it to some wiring. I can't remember how the relays are, but maybe the box comes apart the relays and fuses are in to allow you to dig deeper into the wiring, that's definitely where I'd go from this point.

I wouldn't get rid of it, if its just a relay issue, runs and drives great, and the body is good. They're getting hard to find in good condition.

I just got an 88 B2 about a month ago, waiting for the shop to put it back together so I can bring it home and kind of work on stuff on it myself as I get time and money. I don't want to get rid of this one, I think I got a hold of one in much better body condition. I'll keep plugging away at mine.

I'm not sure if the 86 and 88 had the same fuse and relay setup, and I don't have my B2 close to look around and give you some ideas.

 

[The Slider]

Thanks WildBill!!! Yeah, didn't think about turning the key on and then moving wires and wait for the relay to click. Just have a lot going on. Next time it goes out i will do that.

 

[little red ranger]

Sometimes the socket where the relay plugs in will become dirty and corroded ,,, try unhooking battery neg and spraying the socket with a good electrical cleaner wait half hour or less and plug in relay and hook battery back up,,,might help,,,, if not this link on wiring might help you out,,, it is a to z and many years of diagrams,,, great link to save and pass around ,,,, http://www.revbase.com/BBBMotor/Wd

 

[The Slider]

Well It all started again! NOW wiggling wires are not working... I tracked the relay wires... The Relay Clicks but NO fuel Pump! There is a Green wire that goes down the Passenger side firewall... and the 2 red wires are connected to a connection close to the relay... the Black wire dissapears into a loom...

The Relay is clicking... but the Fuel Pump is not engaging... Can someone give me a clue to were to go??

Thanks!
Chas

 

[The Slider]

I took a picture of the bottom of the relay... the RED wire at the top left has constant 12v when the key is on... I have NO power at ANY time on any of the other wires.. I changed the relay and still nothing.. I tried having someone turn the key and checked the other wires for the 2 seconds the fuel pump is supposed to have power and Nothing.. I also checked the codes and I got a Code 87 ((O) Fuel pump circuit fault (check inertia switch))
I have NO power to the inertia switch...

Any help would be great!

Thanks!
Chaz

 

[IIBRONCOS]

I have had a few electrical items stop working on my B2,and most of the time it turned out to either be a wire that looked good but the copper strands inside were all broken, or a badly corroded wire connector. I wiggled a few wires on connectors like yours and have had them pull right out of the connector. They look OK from the outside but can be ready to break off.

 

[wildbill23c]

Bypass your inertia switch temporarily, that could be your culprit. Mine failed on me a while back, it was so touchy that if you hit the brakes hard it would trip the stupid switch.

A bad fuel pump relay could also mean your fuel pump is failing as well pulling too much power and causing the relay to fail. Just had that problem in my 88 B2.

 

[The Slider]

Bypass your inertia switch temporarily, that could be your culprit. Mine failed on me a while back, it was so touchy that if you hit the brakes hard it would trip the stupid switch.

A bad fuel pump relay could also mean your fuel pump is failing as well pulling too much power and causing the relay to fail. Just had that problem in my 88 B2.

I have no power going in or out of the Inertia switch..
I heard there is a ground for the Fuel pump relay. Any Idea where it is located?
Also can someone tell me what each wire does?

Thanks!
Chaz

Funny how the Chilton and Haynes manual have different wiring schematics.

After looking at the EEC connection wire. This might be the EEC relay NOT the fuel pump relay... Going to verify that tommorow. This relay would never mount the way it was supposed to on the firewall, and thought it was the fuel pump relay... My memory is getting old... just like my dear ole Bronco II!

 

[The Slider]

*UPDATE* In case anyone cares...

I have been messing with the EEC relay all this time. I put a fuel pump relay in the EEC connector. I swapped the relays and it fired right up. unless it was a coincidence. I ordered 2 new relays and 2 new connectors from NAPA.

Now my new questions is..

What happens if you run a fuel pump relay in the EEC connector? According to NAPA, they are not the same.. I have noticed for a while it was running kinda sluggish... Don't know if that is the problem or not..

Thanks!
Chaz.

 

[wildbill23c]

The wrong relay may be a lower amperage rating, or something similar.

I had a similar issue with my 88 Bronco 2. The fuel pump itself was failing and drawing too much power and as a result the fuel pump relay became intermittent and finally failed completely. So if the relay is giving you trouble it may be a good idea to swap that fuel pump because if its bad it could cause you to have continual relay failures in the future.

 

[The Slider]

Ok... I have 3 relays attached to the passenger side fenderwell... the green one is the fuel pump relay... the brown one is the EEC relay.. WHAT is the 3rd (Black) one for?? I am thinking WOT... But I can NOT find any schematic in a haynes or chiltons or the internet.

I have ALL my relays confused, But I'm going to change all the relays and connectors, but I have NO idea what the black one does (WOT?) so I can order a new one and a connector


Thanks!
Chaz