Hi there, new to the forum but not new to fox bodies. I do need some help though. I'm converting my 83 fox to EFI by installing a motor out of an 88. I have the complete motor, injector harness, PCM harness and O2 harness. The question that I have is there are a couple connectors on the engine harness that would plug into the 1988 mustang wiring that my car does not have, for instance there are two connectors a black and a gray that would reside behind the driver side strut tower and those connectors would plug into a harness that goes to the dashboard of the 88. There are a couple wires on that connector that I have been told are for engine crank and engine crank/run. what am I supposed to do with those? I'm assuming those would need to be connected to something on my cars ignition wiring?!
There is also a green six pin connector (only 4 pins inside) that is extremely close to the PCM connector that I have no idea what it is for.
Any help would be greatly appreciated. If you have done a swap like this before I would be greatly interested in any advice you could share. I'm sure it cannot be that difficult since I have all of the engine wiring as I have been told by some people it is as easy as supplying power and ground.
Thanks for the info. I believe I have already seen some of the wiring diagrams that he has put together. I was hoping to find someone who has already done this swap and had a diagram of what goes were.
Your best bet is to do two things:
1.) Buy a Chilton manual for an 88 Mustang - it will have the wiring diagrams which have the connector shapes and wire colors.
2.) Post a detailed description of the connectors and the wire colors associated with them. Photographs of the wire colors are no good, because the color rendition from one computer to another is not the same. What looks hot pink on one computer looks like red on another computer.
Maybe my first post was a little misleading. In one of the photos that I posted there are 2 connectors one black and one grey. The grey connector has 2 wires in it that are for engine crank and engine crank/run. My question is do I need to connect those to any of my original 83 wiring for the engine to run? If so what original 83 wiring would I tap into?
It's tough to identify thpse plugs without reference as to where in the engine bay they would be located. I can think of several plugs that they look like, but without knowing what the location of the plug would be in, it's tough to say if it's needed or even what it went to.
Here is the wiring for a 1988 drivers rear apron area
What you are holding in your hand is C403 and C201, and you are right, they tie back into the dash harness that runs inside a 1988. Inside those plugs, are wires for the low oil relay, the neutral sense circuit, transmission wiring such as the VSS and other wires which aren't present on your early Fox mustang. You are going to need some of these to get the engine to run well.
I'm not familiar with EFI swaps, but I'd imagine you'd want to get two pigtails from a 87+ car that plug into these with 6" of wire, and a 1988 EVTM like I have here, and start tracing some wire colors out.
That's a Mass Air harness that requires a different computer and a MAF, use a A9L, A9P and a MAF.
94-95 Mustang GT MAF - $40-$100. It is 70 MM instead of the stock 55 MM on regular stangs built prior to 94. This is a direct one for one swap that does not require any tuning or programming, It uses a slip on duct on the side that goes to the throttle body and a 4 bolt flange on the other. You need a flange adapter to fit the stock slip on air ducting that goes to the air box. Wiring plugs right in with no changes. *1 *2
*2.) MAF & sensor interchange
The 94-95 Mustang 5.0 MAF & sensor is also found on:
1995-94 Mustang 3.8L F2VF-12B579-A2A,
1994-92 Crown Victoria 4.6L F2VF-12B579-A2A,
1995-94 Mustang, Mustang Cobra 5.0L F2VF-12B579-A2A,
1994-92 Town Car 4.6L F2VF-12B579-A2A,
1994-92 Grand Marquis 4.6L F2VF-12B579-A2A,
Evidently the –A1A, -A2A, AA, etc. on the end of the part number is a minor variant that did not change the operating specs. You should be able to ignore it and have everything work good.