1983 GT engine / firewall wiring ?

[5ohFFR]

I've been driving myself crazy with the wiring. The previous owner lost the engine wiring harness. I have the factory Ford manuals and finally figured out the apron wiring pictures in the manual don't match my setup. The manual shows a big square plug near the Duraspark box, but I didn't have that on mine. I found that square, grey connector up on the firewall in the middle. There also is a two-prong connector there next to it that is the same as one of the ones on the Duraspark box.

Can anyone with an '83 similar to this help me out? Now looking at my wiring, it doesn't even look like the harness Fox Mustang Restoration sells is going to help me at all.

[grtskydog]

I'm referencing my '85 for this, as I've been rewiring under the hood myself...yours my be different, but knowing Ford I doubt it. The 2 -terminal roundish one is the D-spark ignition "start/run" signal. The square one next to it should be a 8-pin terminal. This one connects the following (among other things):

-temp sender
-oil pres sender
-low oil sensor
-tach signal
-a/c compressor trigger


EDIT: Found it. Here's the link to get the '83 wiring PDF. These are great PDFs and have pictures of the factory terminals, and in some cases where they're located.
http://vb.foureyedpride.com/showthre...ht=1985+wiring

[grtskydog]

Also, these guys http://www.fmsiinc.com/terminals4.htm have the proper terminals to rebuild/rehab the factory plastic connectors. If you don't have the factory ones and someone has used that Radio Shack Molex, well, then you're off to the junkyards .

I like the factory pieces, since they have little wedges in them that pop out and allow you to release the old wire terminals for rebuild.

[5ohFFR]

Thanks Ed. It's looking more and more like I will have to make one myself. I have a used 8-pin that matches my '83 from an '85 harness that I have. The '85 harness is mostly bad, melted in places, cracked insulation, cut wires, no ends, etc.

[ElaborateDream]

No no, that's normal ford wiring.

I've got an 83 with most of a stock harness under the hood. If you need specific pictures, I can head out to the garage and take a few snaps.

[grtskydog]

If the plastic connector part is in good shape, you're fine. Just pick up some terminal pins for it and some new wires and rebuild the thing yourself. If I can do it anybody can.

[5ohFFR]

No no, that's normal ford wiring.

I've got an 83 with most of a stock harness under the hood. If you need specific pictures, I can head out to the garage and take a few snaps.

Where I am the most confused is on the driver side apron at the Duraspark box. Do the two plugs off the Duraspark connect to the main harness there? Where does distributor wires (off the 3 prong plug) run to? What exactly connects to the two-prong plug next to the 8 pin female plug off the main harness at the middle of the firewall?

I hope I'm not being to much of a pain in the !@# .

Thanks!

[grtskydog]

The 2-prong plug next to the 8-pin is for the Duraspark. It is the ignition start-run. The 3 prong from the distributor goes into the engine harness (that I take it you don't have) that then plugs into the 4-prong at the D-spark box. If you are going to make your own engine harness that works with the D-spark box, that plug (4-pin female I think) that goes to the box will be the tough one to find, especially in good shape (the wiring is molded into the connector, not quick-release like the 8-pin). If there is a way to repair/build one of these types, I'm not aware of it. The other possibility is to get the "weather-tite" 4-pin connector from Summit/Jegs and make a new connection on both ends of that particular connection. You can build your own engine harness, it just takes a little patience, soldering, and parts-hunting to do right.

I'm on the road right now, but if you like, I can try to bitmap you up a simple diagram of how my 85 engine harness is wired...I have all that stuff drawn up at home. Keep in mind, I don't use the a/c "kicker" solenoid on the carb, or the "horseshoe" connector on the coil (I have a Blaster 2). If you can make reasonable sense of the wiring diagrams, you can actually build it that way, too.

[5ohFFR]

The 2-prong plug next to the 8-pin is for the Duraspark. It is the ignition start-run. The 3 prong from the distributor goes into the engine harness (that I take it you don't have) that then plugs into the 4-prong at the D-spark box. If you are going to make your own engine harness that works with the D-spark box, that plug (4-pin female I think) that goes to the box will be the tough one to find, especially in good shape (the wiring is molded into the connector, not quick-release like the 8-pin). If there is a way to repair/build one of these types, I'm not aware of it. The other possibility is to get the "weather-tite" 4-pin connector from Summit/Jegs and make a new connection on both ends of that particular connection. You can build your own engine harness, it just takes a little patience, soldering, and parts-hunting to do right.

I'm on the road right now, but if you like, I can try to bitmap you up a simple diagram of how my 85 engine harness is wired...I have all that stuff drawn up at home. Keep in mind, I don't use the a/c "kicker" solenoid on the carb, or the "horseshoe" connector on the coil (I have a Blaster 2). If you can make reasonable sense of the wiring diagrams, you can actually build it that way, too.

Thanks! I got a Duraspark engine harness from a Ford pickup and matched up most of those wires with the plugs. Now it just seems my only problem is figuring out the coil wiring (the harness was hacked up there) and that grey 8 pin connector from the middle of the firewall. The PDF wiring harness for 1983 doesn't show the 8 pin connections for the V-8, only for the 4 and 6 cylinders. The 8 pin connector must connect the water temp and oil pressure senders and maybe the A/C? I know it also connects some emission crap that I don't need.

[grtskydog]

I've got all that written down at home. If I remember right, the 8-pin does have a couple of emissions components. The coil actually connects there as well. I suspect it's coming from the ballast resistor somewhere. The coil wiring interacts with the distributor in the engine harness. I'll try to look at all that stuff when I get home this weekend.

[83 V8 RS T's]

Here is a start.I will work on a diagram on the wire color and pin location soon.This is the motor harness.


This is the main harness at the firewall.


Here is the duraspark connectors


Does any of these look like they might help?

[83_BossGT50]

Good luck bro! Iv been looking for that harness for a few years. I finelymade one of my own you can get one of a crown vic or truck but it wont have the tach whire. GOOD LUCK

[grtskydog]

On the '85 there's another 8-pin terminal that connects the "diagnostic center" on the console. If you're not using it anymore, you can "borrow" that one and build a new engine harness with it.

[5ohFFR]

I have an 8 pin grey connector from an '85 GT. The rest of the wiring was cut or melted though. Once I get the pins correct on the grey connector, I will probably just have to make a harness but I think I will be ok after that.

[83 V8 RS T's]

I hope this looks o.k.This is how my 83 Capri is wired.

[5ohFFR]

Bob,

Thanks a ton! I really appreciate it. I will compare this against mine tomorrow night, but this should get me finished.

[5ohFFR]

I hope this looks o.k.This is how my 83 Capri is wired.

Well I spent about 2 hours tonight (yes, this is what I did on a Saturday night - I feel like I'm 14 years old again , but my wife was out shopping) doing a prehistoric fossil dig on a harness I got out of a dead '83 GT. I only have two wires on the engine harness 8 pin connector that I can't figure out where they go:

(1) Black - Yellow Hash
(2) Red

Here is what I figured out: (anyone please feel free to correct me)

Green - Purple Hash = Carburetor fast idle or something
Red - Green Stripe = to coil
Red = ?
Black - Yellow Hash = ?
Red - Yellow Hash = WOT A/C cutout on carburetor
White - Red = Oil pressure sender
Red - White = Water temp sender

I had a couple of connectors still on the old harness, especially the carb ones, so it made a few things easy.

[grtskydog]

The BK-Y H wire goes to the (+) side of the a/c compressor clutch. From what I could tell on the '83 wiring schem. the solid red also goes to the WOT cutout switch at the carb.