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El Chapo

Electric issues

Recently acquired a 86 bronco xlt with 5.0 EFI automatic transmission. It’s a solid arizona only truck so no rust and otherwise in fantastic shape.

So my frustration is that since it was parked for 10 years I decided to replace the entire full system including: tank, sending unit, high pressure pump, filter and inspected and replaced the donut filter in the fuel reservoir. I hope i put everything back correctly ha! Problem is that the pumps don’t click on so it doesn’t start, with external power source the pumps do click on but not with the ignition. I can’t find fuse link “S” to check or the fuel shut off / relay r for that matter anything else related to getting the fuel pumps going

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

Gary Lewis

Re: Electric issues

Administrator

Welcome! Glad you joined.

Where's home? I ask because we have a map (Bullnose Forum/Member's Map in the menu) and we can add you with a city/state or zip.

I look forward to seeing pics of your Bronco.

As for your electrical problems, you really need to start a thread in the main section on that as it'll get more attention there than here. This folder is really just for introductions.

So, would it be ok if I moved this to the main section? Meanwhile I'll attempt to answer your questions in my next post.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

Gary Lewis

Re: Electric issues

Administrator

You are going to have to get very familiar with the 1986 EVTM - Electrical & Vacuum Troubleshooting Manual. It is a Ford document and is available here: Documentation/Electrical/EVTM's/1986 EVTM.

Once going there you have to pick the section. In this case you need these sections:

Electronic Engine Control: This gives you the schematics specific to the EEC system.

Electric Fuel Pump Control: Schematics for the fuel pump's circuits, including on Page 107 an illustration showing where the fuel pump cutoff relay is - near the brake booster. But don't miss the inertia switch in the feed to the relay. It is near the passenger's left foot and if it trips there is no power to the pump, even if the relay works.

Charge/Power Distribution: Shows the power circuits, and on Page 15 it shows that Fuse Link S attaches to the starter relay.

Gary, AKA "Gary fellow": Profile

mat in tn

Re: Electric issues

maybe I picked up on something. maybe it's just a slip. did you replace a sending unit or a pump/sending unit?

El Chapo

Re: Electric issues

In reply to this post by Gary Lewis

Yes please move it to the main folder, I live in Phoenix

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

Gary Lewis

Re: Electric issues

Administrator

Moved and mapped.

Gary, AKA "Gary fellow": Profile

El Chapo

Re: Electric issues

In reply to this post by mat in tn

I did replace the sending unit in the new tank and the inline pressure pump, after it sat DE6E5210-A800-4A34-9944-E902ABAB791C.jpegfor so long the fuel in the old tank smelled like turpentine and the old sending unit was corroded severely.

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

El Chapo

Re: Electric issues

In reply to this post by Gary Lewis

Yes thank you I have see that document it’s great but as a old beginner like me I still get confused as things don’t seem to match what’s on my truck, the previous owner claims nothing funky was ever done to it so should all make sense. I’ll send pictures

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

Gary Lewis

Re: Electric issues

Administrator

When you post the pics you should walk through the Insert Image dialog instead of posting a link. That way the image is permanently part of this forum even if where you have it stored goes away.

For instance, I just copied your link and pasted it into the line shown below, after wiping out the "http://" that is already in there.

And I got this:

Gary, AKA "Gary fellow": Profile

mat in tn

Re: Electric issues

the sending unit in the picture is an in-tank pump/sending unit. it contains a priming pump to get fuel to the main line pump which will build pressure but not prime itself. did you install a new one with a pump?

mat in tn

Re: Electric issues

I see that you said that earlier, sorry. there is a line of contacts which are made in getting the pumps to come on. key switch sends voltage to the ecm relay, then ecm sends voltage to the inertia switch, the inertia switch sends voltage to the fuel pump relay for 3 seconds until continuous run is detected when it sends voltage continuously.

El Chapo

Re: Electric issues

I have failed to mention that aside from the fuel pump not clicking on, the instrument panel is dead emissions warning light goes on for a few seconds, clock seems to be fine. previous owner says he worked on the steering column I'm concerned about some funky stuff going on there too :(

I did seem to locate the inertia switch passenger side under the dash. It reads: 1st inertia switch the white tab on the top seems loose when depressed, not sure how that gets reset or needs replacement.

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

mat in tn

Re: Electric issues

do you have tilt wheel?

El Chapo

Re: Electric issues

Yes tilt wheel

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

mat in tn

Re: Electric issues

since you have tilt wheel. how loose does the ignition feel? the actual ignition switch mounts on top of the column under the dash. there is a linkage rod that connects the ignition switch to the key cylinder. on tilt wheel columns there is a small interconnect link called an actuator. all this means is that there is a chain of events when you turn the key. it possible that the ignition switch is bad, not settling in the proper position or even a broken actuator link. just a few things to check

El Chapo

Re: Electric issues

Thanks I'll check into that.. The key seems sticky and it's hard to turn.

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

mat in tn

Re: Electric issues

i recently had a truck here where someone had a broken tab for the turn signal connector (crescent shaped plug next to ignition switch) and rather than leaving it to dangle or rattle they zip tied it to the column. all work seemed to have been done well except that from underneath you cannot see the rod that goes between the key cyl and ignition switch. it was in a bind with the tight zip tie and did as you describe.

El Chapo

Re: Electric issues-continued

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

El Chapo

Re: Electric issues-continued

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

El Chapo

Re: Electric issues-continued

In reply to this post by El Chapo

86 Bronco XLT “La Bronkita” Tow/light pkg. 302/EFI, BW1345

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