efi conversion

[Greg]

Looking for someone who may no the particulars of connecting a scavanged efi system to a older vehicle. Have a 68 mustang and looking to wire in a fuel injection system. Have a ford racing harness and a partcial harness from a 91 mustang 5.0 5sp. Specificly I am looking for what wires are used to power the system.:confused:

[C7Z]

Looking for someone who may no the particulars of connecting a scavanged efi system to a older vehicle. Have a 68 mustang and looking to wire in a fuel injection system. Have a ford racing harness and a partcial harness from a 91 mustang 5.0 5sp. Specificly I am looking for what wires are used to power the system.

I don't know what your skill level is with regards to this conversion, so lets start with the basics.... You need all 3 harnesses to make a EFI system work correctly, the injector harness, main engine harness and the O2 harness. You also need all of the sensors such as the MAF meter, O2 sensors, ACT, water temp, etc... ( You do not need the TIB TAB TAD or EGR position sensor, but you may get codes for them ). You also need a computer for a automatic ( or for a stick if you are using a stick ). Yes, you can use a stick computer with an automatic if that is all you have, but you may not be able to pull codes and could very likely have drivability issues, but it will run.

Not all 5.0 Mustang wiring harnesses are the same either. The speed density harness was from 1986 - 1988 ( 1987 in CA ), the MAF harness changed slightly in the 1991 model year, the primary change was to eliminate the grey and black connectors by the power brake booster and replace them with a single reddish brown connector, however the color codes of the wires remain the same. I believe that some circuits may have been relocated to the green plug by the EEC from the grey and black plug as well.

So, you need to identify which style your 91 harness is ( grey/black pug or reddish brown ). I believe that the Ford Racing harness is the reddish brown variety.

My first reccomendation is BUY A FORD EVTM for the year of Mustang that your harness is from.
If you don't have a copy of the installation instructions for the Ford Racing harness, you can view the PDF of it here : http://www.fordfuelinjection.com/files/M-12071-A50.pdf

Here is what you need to connect :

Wire Color - Circuit - Purpose

Green plug by ECU

Grey/Yellow - 687 - Key on 12V for oxygen sensors
Pink/Black - 787 - to fuel pump relay and sending unit from ECU
Orange/Yellow - 563 - to vehicle speed sensor from ecu
Tan - 657 - to check engine light from ecu
Green/White - 150 - to vehicle speed sensor from ecu

Grey Plug

Dark Green/Yellow - 11 - to tachometer
White/Pink - 258 - to low oil warning relay ( unused )
Red/Light Blue - 32 - to S terminal on starter solonoid ( 12v in start position )
Red/Light Green - 16 - to 20ga fusible link to 12v key on ( run )

Black Plug

White/Red - 31 - to oil pressure gauge
Red - 361 - to fuel pump inertia switch to circuit 97 ( back to this plug )
Tan/Light Green - 97 - to fuel pump inertia switch to circuit 361 ( back to this plug )
Red/White - 39 - to water temp gauge
White/Purple - 26 - this circuit needs to see a ground when used in a automatic and the transmission is in N or P and NO ground when in gear. In a stick-shift application, it needs to see EEC signal voltage in Neutral.

Like I said, if you use a harness with the reddish brown connector instead of the grey and black ones, some of the wire locations have been moved around but the colors and circuits are the same.
I have converted my 65 Mustang to EFI, my 83 Capri to EFI and am in the process of building my 1980 Mercury Zephyr with EFI. It is time consuming and can be frustrating but you will not reget the results !

If I have overlooked anything or if you have any other questions, feel free to ask.

Good luck and have fun !
-D Payne

[shawn123]

hi dear,...
great informative post with very helpful link shared,..
looking great car,..
thanks,..