ECU and Harness swap

[kgatwood]

I have recently had a new engine installed in my 1988 bronco xlt efi. Both the new engine and old one were 5.0L. When I look at the specs required for the new cam it indicates that the stock ECU is not compatible so I have done some research and an A9L ecu is what I will need to have the engine run smoothly. I have in my possession both the A9L and the main wiring harness from a 1990 mustang GT. Can anyone tell me if the wiring harness from the mustang can be swapped for the existing stock harness?

 

[Rons beast]

Possibly some of the components will plug right in, but because of the difference in design, and size of the 2 vehicles, everything may not fit. But if you are really good with wiring, it could be made to fit.

 

[kgatwood]

I can probably do that. You will have to excuse my ignorance on this issue so this might be a dumb question. Do the wires of same color in a harness do the same thing and are wiring color schemes consistent from an 88 to a 90? What I am thinking of doing is to create my own harness out of the 1990 which would entail using the connectors from the old harness and simply connecting the new harness wires in to them. For example if the old harness had a connector with a yellow wire, a red wire and a blue with yellow strip wire, then I would take that connector off and find the same wires with the same colors from the new harness and mount them in the connector. Would this work? What would I do if there are wires left over at the end that haven't been included in any connector simply because I think the 1990 has more wires than the 1988?

 

[Rons beast]

Can't say the wire schemes are the same. My books show some differences between the years, and some things constant. If you want to tackle this , get a wiring diagram for each year and compare as well as compare to what you have on the truck. There may have been things changed by a previous owner.

You sound like you are on the right track, and are competant to do the job.

Keep us informed on the progress. It could help others.

Good Luck

 

[miesk5]

yo,

Here are many wiring diagrams and connector pin-outs and tests (without colors but you can figure it out by looking at connector pin out diagrams and test for continuity in ground wires or test for 12v;

Ford Fuel Injection and Electronic Engine Control: How to Understand, Service and Modify, 1988-1993; Scroll Down on First Page, Click on each Section, then on next page, click on the pdf file; the complete book is over 85MB pdf and can be downloaded @ http://www.yunost.ru/docs/Ford-injectors-book/Book.pdf

Chapter 12-4 has many EEC IV Pin-Outs (Partial) in 88-89 & 90-91 Bronco 4.9; 88-90, 91 & 92-93 Bronco 5.0; 88-91 & 92-93 Bronco 5.8; Looking Into Harness Connectors [/url]88-90 Bronco 5.0 on page 395

http://www.yunost.ru/docs/Ford-injectors-book/Part12/Part12-4/Part12-4.pdf

but the stang's are just for the 2.3 as far as I can tell because, my ISP is so slow, trying to open other chapters/pages is impossible so ldownlopad the entire Book pdf to you PC for faster access

For more Bronco wiring diagrams, but w/color codes and conn pin outs; see my site @ http://www.broncolinks.com

got to Electrical section and Sensors... see other component setions as well, such as the Emission Section for TA/TAB, O2 sensor etc.

Next is RJM Injection Tech(by Ryan M (Fireguy50)) - Bronco/Ford truck EFI parts, EGR Eliminators & tubes, alternators, starters & cables, sensors, harnesses, pigtails & connectors including WeatherPack connectors, relays, tools

Ryan M has the 5.0L Universal Harness "...designed for Cobra Kit cars and other hot rods seeking fuel injection supremacy. Swap a 5.0L/5.8L engine into your vehicle using the popular & unbeatable 1989-93 Mustang 5.0L technology. Lay in it, connect 3 wires and it runs! Its superior design only draws 0.7amps from ignition switch, which minimizes the stress on older vehicles. Built in the U.S.A. with Brand New OEM Ford connectors and 260°F GXL ..."

 

see instal kit instructions for connector ID

http://96.0.50.30/harness_manual-K.pdfhttp://96.0.50.30/harness_manual-K.pdf

 

 

 

For Stang wiring diagrams; aside from Googling;

 

Repair Guides & Wiring Diagrams (click vehicle, year range) & go to Chassis Electrical & scroll for Wiring Diagrams...(under license from Delmar Publishers, comb of Chilton/Nichols/Delmar & Haynes); some may be incorrect, as reported by Seabronc, thanks Seabronc! NEW SITE URL!!! MUST REGISTER TO VIEW; select year, make, model, engine size and go to appropriate section

Source: by Chilton via Autozone http://www.autozone.com/http://www.autozone.com/

 

Auto Repair Reference Center Repair Manual, Mostly Chilton; many local library's offer free online access for their members; just log-in w/your library Card # and password; incl. all Broncos, & many MAKES! 1951 to current; some years (85-Current, I believe) include: FULL Technical Service Bulletins and Recalls, Labor Hours per repair (plug in appl info); some Wiring Diagrams, Vacuum Diagrams (in DRIVEABILITY AND EMISSIONS CONTROLS Section), Specifications (torques, etc.) & Maintenance Intervals

Source: by arrc at http://search.ebscohost.com/http://search.ebscohost.com/

 

Our Library switched from ARRC to Chilton on-line in past, but has now switched to Mitchell, but it is in-library use only... it is the BEST non-Ford info available!