Bullnose Enthusiasts Forum

Engine harness rebuild 5.0 efi

Classic

List

Threaded

28 messages Options

Kyle_christina

Engine harness rebuild 5.0 efi

Hey guys, i have been hanging out here for a bit without doing much posting. Thanks for all the information and work you guys do here on this forum! Now for the questions. As the description says, i am rebuilding my harness which seems to be the best option. I have sourced pins for some connectors but not all and some pig tails(mostly from rock auto). Is there a better source for these electrical connectors and especially eec terminals? I found eec terminals on ebay but the seller thinks they are worth gold at 10 bucks for one terminal..... also i need to replace the inline 22k ohm resistor that comes off of pin 4 in the ecc. I am not sure how to go about it. I can only seem to find bare resistors and nothing like the incased one that is original. So sorry for the long winded post but i want to be as thorough as possible. Also for wire i am only going to use about 4 different colors and its going to be marine grade ancor wire from amazon. I was thinking blue for signal, black for ground, green for common, and red for power? Does that seem like a good idea?
Reasoning behind this is because it is already going to be expensive enough so i want to simplify. Thanks again! 22k ohm resistor

1986 ford f150 2 wheel drive
302 modified
Bored .40 over dished pistons, windsor jr heads,
Performer camper cam, hardened push rods, roller rockers,
Double roller timing chain and stock intake (ran out of money at age 16)
Needs alot of work still.

Kyle_christina

Re: Engine harness rebuild 5.0 efi

Also it seems as though most wire is 16awg with some 14 awg or 12 awg sprinkled in for power and ground. I dont have a great way of measuring other then with my wire strippers.

Vic Roma

Re: Engine harness rebuild 5.0 efi

Good luck with this - ambitious project. I was thinking of doing the same thing but believing I wouldn’t find all the connectors, I thought of using newer water-proof connectors or something similar, with sheathing to protect wires against abrasions, etc.

Did you consider replacing old connectors for new? Are you sticking to old style to keep the truck original? Before I botch my harness, I wanted to *gauge* what others think.

As for determining wire gauge, you can calculate it yourself. Google will tell you many things but here is an example:
https://m.wikihow.com/Gauge-Wire

1984 Bronco 351 Holley Sniper EFI, 3 Speed Ford Auto.
1986 Bronco 302 EFI, AOD, Eddie Bauer, with 3G alternator.

Kyle_christina

Re: Engine harness rebuild 5.0 efi

I am trying to replace as many connectors as i can with original. I would love to update all the connectors to more modern stuff. I have access to a vast amount of different styles, however most of the sensors have the connector molded directly on them such as the knock sensor. For that reason im trying to keep that part original. The truck it self is far from original so its not much of an issue for me. I just simply have to rebuild the harness out of necessity. There is insulation peeling off wires all over the place. With that i am also replacing a few sensors that havent been yet. I found a harness on painless that us for if i remember right an 87 to 91 mustang for 600 bucks. Thats really expensive to me and i would have to change to maf. The goal is to not have this engine in here for ever either so i do not want to upgrade to that system. I just want this one to work for the next few years. I will give that website a look for determing wire size. Thanks again

85lebaront2

Re: Engine harness rebuild 5.0 efi

Administrator

I have found some good sources for some of the connectors, EEC pins, there was a place, but I think he is out of business. On most of the other stuff, Motorcraft has a lot of the pigtails and their catalog is on this site. If you get the Motorcraft number, then go onto Rock Auto and use the Part Number section, it's a little annoying, but you can find it if they carry it. The molded ones, like the EFI to front harness interface, you can get replacements, but will still need to splice them in. If there is nothing wrong with the resistor, why change it? I suspect it is in the tachometer wire.

DO NOT use crimp connectors, wrap splice, solder and use heat shrink tubing over it. On retaping the harness, use friction tape, it will hold up better. The corrugated sleeving that a lot of it is in, can be purchased, or I have a load of it from salvaged harnesses.

The larger pin connectors, round and flat 1/4" are readily available aftermarket in Dorman products Help line. I have PNs for those. I also have extra 60 pin EEC plugs (which can be a pain as the little retainer tabs break if you look at them wrong).

Be glad it's a Ford and not a Chrysler product, at least your parts are available.

Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

Gary Lewis

Re: Engine harness rebuild 5.0 efi

Administrator

We have a link in the Resources/Electrical to Ford's connectors and pigtails catalog. You might be able to find the connectors in there, get the part numbers, and find them on-line to order.

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

Kyle_christina

Re: Engine harness rebuild 5.0 efi

I appreciate the feedback. The reason i want to replace the resistor is because the insulation on the wires going into it and out of it are peeling off right up to the resistor. Other wise it is fine. It reads 21.7 k ohms actually. Im not sure how to track down the part number for each connector. It does not seem easy to do by any means. I did look through the catalog some. But like was mentioned its not that easy without part numbers. I will have to spend some pain staking time figuring that out. I do know my harness is going to have extra splicing since some pins and terminals are not easy to come by. It wont be that pretty but its going to function a whole heck of alot better and i will not have to worry about shorts happening. I do need an eec connector. Pin 20 melted into the connector.

Gary Lewis

Re: Engine harness rebuild 5.0 efi

Administrator

Several things. For connectors you can't find in Ford's catalog I'd suggest going to the salvage - several of them - and buying portions of harnesses as needed. Then, graft them in as Bill suggested - solder things and use adhesive-lined shrink tubing to seal the joints. I like kits like this one: https://www.amazon.com/130-pcs-Adhesive-Assortment-MILAPEAK/dp/B071H5XC7C/ref=pd_lpo_vtph_468_bs_t_1?_encoding=UTF8&psc=1&refRID=PHJWVN600BRVV1H4WXP5

As for the wire colors, I'd recommend that you leave the factory wire showing at the connectors if you can. That way you can figure out what the circuit is. In other words, go to the salvage and get an EEC connector and as much wiring with it as you can. Then replace what you need to on your harness, but if the wires aren't long enough splice in a common color - between factory wires.

On the resistor, you can get a common resistor and encase it in the shrink tubing already mentioned for protection. And assuming that it is just in a sensing circuit a common 1/4 watt resistor should work.

Gary, AKA "Gary fellow": Profile

Kyle_christina

Re: Engine harness rebuild 5.0 efi

If i can leave factory colors at the connectors i absolutely will. Thanks for the advice on the resistors. Another thing i might do is label each wire part way through with a labeler that can label shrink tube. I will definitely take all the advice i can get. Im pretty comfy with a solder iron and protecting electronics, just my experience is in a more industrial setting. The good thing is that my f150 is my toy and i can spend time finding what i need to do this right. I appreciate all your feedback. I will try to document my work and findings here. It is going to take me a while though. I am busy with my wife and 2 boys!

Rembrant

Re: Engine harness rebuild 5.0 efi

A tip of the hat to you for tackling the project of rewiring an 86 EFI truck. That is a daunting task to say the least.
I just recently took one of these trucks apart and sent the EFI harness and all related EFI components to a fellow forum member for spare parts.

I remember how well these EFI trucks ran when they were new, so if you get it all fixed up it will be worth it, but it's still a big job.

Good luck. I'll be following along out of curiosity.

1994 F150 4x2 Flareside. 5.0 w/MAF, 4R70W, stock.
1984 F150 4X2 Flareside. Mild 302 w/ 5spd. Sold.
1980 F150 4X4 Flareside. 300i6 w/ 5spd. Sold in 2021.
1980 F100 4X2 Flareside. 351w/2bbl w/NP435. Sold in 1995

Steve83

Re: Engine harness rebuild 5.0 efi

Banned User

In reply to this post by Kyle_christina

Kyle_christina wrote

Does that seem like a good idea?

No. It will get really-confusing really fast, and when you have problems later, it'll be nearly impossible to figure out.

Striped wire isn't common, but it IS available & affordable. I keep several of the ones that either match or are similar to Ford colors so I can modify & repair harnesses (which I do often), so I haven't ordered any in a while. There are a few sellers on eBay & Amazon, and it takes a little effort to find them, but it's worth the effort.

Another good source is any Ford product in your local JYs. That's probably also the cheapest & best, and you're guaranteed to get Ford colors & quality.

It's the CONNECTORs that you should thinking about changing - not the wire colors. Don't feel like you have to keep using those antiques that weren't very good to begin with. Newer connectors are MUCH better; often having Gold-plated terminals. Just avoid the tiny ones that are difficult to re-pin.

85lebaront2

Re: Engine harness rebuild 5.0 efi

Administrator

I agree completely, I salvage harnesses and parts of harnesses every chance I get. That way I can usually match the original colors so it is easier to follow (try working on a 1970 Rover 3500, all the wires were white with cloured tubes at the ends).

Bill AKA "LOBO" Profile

Kyle_christina

Re: Engine harness rebuild 5.0 efi

I am definitely trying to get new connectors for every sensor/ electrical device on the truck. I will definitely take another look at getting the right colored wire for each circuit, however i am not going for complete oem restore on this harness and i want to do it affordably. I need approximately 300 feet of wire. Ancor wire is around 22 bucks for a 100 feet, so thats why i was just going to use a couple colors. I want to get good wire and not necessarily all of the o.e. colors. I already know that alot of the cost is just in buying each pigtail and or bare connector if i can get it. Most of my original connectors are missing the retainer clips and are really grimey. It would be nice to get all new stuff. Anyway regardless of color wire i am going to label each circuit with a labeler so troubleshooting, if there were to be any shouldn't be too difficult.

Kyle_christina

Re: Engine harness rebuild 5.0 efi

Sorry for multiple posts, i am terrible at remembering what everyone's comments are lol. Our area (dubuque,ia) is a baron land for older vehicle junkyards. We kind of have a you pull it, but they do not have any 80s fords in their yards so that is a bit of a bummer here.

85lebaront2

Re: Engine harness rebuild 5.0 efi

Administrator

In reply to this post by Kyle_christina

Tell me which connectors you need (I sent you an email through the site) and if I have good spares, I can help you there.

Bill AKA "LOBO" Profile

Kyle_christina

Re: Engine harness rebuild 5.0 efi

Thanks for the prompt response. I just saw your email. I really appreciate your help! Right at the moment i will have to wait until tomorrow to tell you the comprehensive list. The harness is at work and so are my lists. I do know i need an idle air control motor connector, knock sensor connector, and charge air temp connector. I could probably just buy the dorman pins for those last 2 connectors though. They are still in decent shape.

Steve83

Re: Engine harness rebuild 5.0 efi

Banned User

In reply to this post by Kyle_christina

Kyle_christina wrote

...i am not going for complete oem restore on this harness...

Right. But the original colors are the ones that will be described in wiring diagrams & troubleshooting procedures. So it's VERY beneficial to keep the correct color for each circuit.

Kyle_christina wrote

I want to get good wire and not necessarily all of the o.e. colors.

You can have both for nearly nothing if you buy JY harnesses from newer Ford products with your truck's engine (like '92-95 F-series/Broncos).

Kyle_christina wrote

...bare connector if i can get it.

What I meant was: don't necessarily try to get the original-shape connectors. Get newer connectors with the same number of pins, that are sized for circuits that pass roughly the same amount of current. Modern pins will be smaller, and modern plastic will be more-durable.

Kyle_christina wrote

...troubleshooting, if there were to be any...

That's like saying "...the sun coming up tomorrow, if that were to happen..."

Kyle_christina

Re: Engine harness rebuild 5.0 efi

I have thought about getting new more modern connectors and there will be a couple which that will happen with, ie where the engine harness connects to the vehicle harness. There are simply to many connectors that are molded into the sensors to try to update them all. I also like the idea of maybe grabbing a harness off a newer truck if i can just repin it back to eec-iv. As i mentioned before i don't plan on keeping this engine in my truck for too much longer.

This could be an unpopular thing amongst die hard ford fans but i do have plans to put a 5.9l cummins under the hood

. Ive seen a few examples of it done already. So short story long, i don't feel the need or motivation to change to a new maf system.

Also what i meant by not having to troubleshoot was with the harness itself. I shouldv'e been a little more specific. I think i have had to troubleshoot wiring in my vehicles maybe once or twice. And that has been with my f150(why im rebuilding the harness). Maybe i have just been lucky with my other vehicles. Once again i really appreciate the feedback and the concern. Today i'm going to do a little research on newer harnesses and possibly getting the correct wire colors.

Gary Lewis

Re: Engine harness rebuild 5.0 efi

Administrator

Kyle - You can still find the EEC-IV system in trucks up until '95, depending on the engine. In fact, the 460's were still running IV through '96 for all but the California trucks. So you don't have to find a Bullnose to get the connectors. However, you might have to re-pin the EEC connector.

Gary, AKA "Gary fellow": Profile

85lebaront2

Re: Engine harness rebuild 5.0 efi

Administrator

In reply to this post by Kyle_christina

You will find a few changes, a couple of pin functions changed in 1987 up, and there were some additions starting in 1998 for the E4OD. Go here for pinouts:http://www.garysgaragemahal.com/efi.html As previously mentioned, I have a few salvaged harnesses, including a 1988-91 pair, and a 1995 one. I can remove as much of the EEC-IV wiring from one of the 1988-91 harnesses and send it to you, I also have a few of the sensor plugs (ECT, ACT, Knock Sensor EGR position etc.)

Bill AKA "LOBO" Profile