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EFI conversion wire harness questions

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Old Mar 3, 2005 | 03:12 AM
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EFI conversion wire harness questions

I need some help with my efi wiring. Its from a 88-87 5.0 MAP that I bought from e-bay. I not sure where these wires hook-up to.
Gray connector near ECU connector with 6 wires:
pin#39,50 SCCS ?
pin#34 DOL ?
pin#6,3 VSS (seperate from the long pigtail the goes to the speed sensor)?

Black connector with 5 wires on same con. as temp, oil gauge:
pin#10 ACCS (I have no a/c)
brown wire w/pink stripe (I think to Ign. run?

Black connector 5 wires on same con. as pin#30 NDS:
Red wire that goes to middle of TFI distributor connector?

My wiring diagram does not specify to any of these.Any help is greatly appreciated!
Mike
 
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Old Mar 3, 2005 | 06:11 AM
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pin#39,50 SCCS- couldn't find anything for pin 39, according to my info, pin 50 would be used for MAF meter only
pin#34 DOL- Data Output Link, not needed, would be used for an on board message center

pin#6,3 VSS (seperate from the long pigtail the goes to the speed sensor)?
3 is VSS signal, and 6 is VSS ground

pin#10 ACCS (I have no a/c)- AC clutch signal, not normally needed, but can be used to raise RPM for increased engine load

brown wire w/pink stripe (I think to Ign. run?- My diagram shows a brown/ pink wire that gets crank and run 12v from the ignition switch and then goes to a fusible link to a red/ green wire that supplies the coil and module.

Red wire that goes to middle of TFI distributor connector?- I am not familar with an all red wire at the distributor. There should be a red/ blue wire that gets a crank signal and a red/ green wire that gets a crank and run signal (also supplies the ignition coil). It is possible that it is the IDM signal (pin 4) which would be connected with a green/ yellow wire which is the - signal for the coil and tach. Should have a 22K ohm resistor inline.

For any of these wires that you're unsure of, I would trace them with a multimeter or open up the harness to determine where they go.

Jason
 
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Old Mar 3, 2005 | 06:46 AM
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How can I find the location of odometer fuse of my Ford Explorer 2003 Model
 
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Old Mar 4, 2005 | 12:28 AM
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hello remonl, there are lots of people here that will try to help you, but you might have better luck posting your thread in the EXPOLORER section under SMALL CHASSIS TRUCKS. good luck..
 
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Old Mar 4, 2005 | 12:43 AM
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thanks Jason. the closest wiring diagram I'm using is from the FORD FUEL/INJ. ELEC.ENG.CONTR. book by charles probst, page #334. 88 mkvii 5.0 MAP-SFI. my seller wasn't sure of vehicle. It shows #39 & #50 to a speed control com. s/w (SCCS)? What ever that is? The extra connector that I have leading to the VSS is a seperate connector from the main plug and the connector to the speed sensor itself. Its connected parallel to the wiring as if to another speed sensor? I just might tape it off.
Next question is some stuff connects to run and some are start/run? Isn't this the same? I'm confused because I've got either start (to the startr sol.) or run(ign on)??
 
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Old Mar 5, 2005 | 06:03 AM
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It sounds like the SCCS is for cruise control operation, maybe set/ resume.
I have a manual that is a little more in depth for the ECM pinouts somewhere, but I haven't been able to find it since I moved. I'm not sure why there is 2 speed sensor inputs, but I think you are safe to cut off or tape up one of them.

Essentially, start/ run and run are the same. But, there is only post on the ignition switch that will be hot in both crank and run which is the 12 v feed to the coil. If you use this wire, you want to tie into it right at the switch because of the built in resistor. There is another wire under the hood that has the same signal without the resistor. It is the green/ red wire that goes to the voltage regulator.

Jason
 
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Old Mar 6, 2005 | 12:27 AM
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The harness that I'm using must be from a car that had some sort of on-board display or like you said cruise control, because that gray connector with all that stuff is right next to the ECU 60 pin connector. So it must have been located on the inside of the dash. Thanks for explaining the start/run and run difference, now I know what to test and connect to when I splice into my existing ign. s/w.
Mike
 
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Old Mar 15, 2005 | 01:15 PM
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I got another question. Do I have to use the water temp sender and oil press. sender wire on the EFI harness or can I use the original bronco wires to connect to my dash gauges? This would seem to be simpler but I'm not sure if the ECU needs to see any of these readings? thanks
 
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Old Mar 15, 2005 | 02:18 PM
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You can do it either way. The wires for the oil press and the water temp gauges are just incorporated into the engine harness to keep it clean. I chose to use my old Bronco wiring harness because the condition of those wires was better and I know they are accurate.

Jason
 
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