efi wiring gurus here please

Hello All,
I am installing efi on my 68 mustang using a 1990 mustang main harness. and i have a couple of questions for you.
on my 90 harness next to the test plugs there is round 8 pin plugs that interface with the cars harness. i need to find out what i need to do with these wires. all the diagrams i have found dont help me with it because they dont give me specifics on what each wire needs as far as power goes. here we go.

BLACK CONNECTOR

blue w/ yellow stripe
wire goes to the o2 harness plug then nothing meaning there is nothign on the 02 harness to plug into. can i jsut remove this wire?

grey w/ red stripe
this wire goes to pin 46 on the eec

wht w/ purple stripe
this wire goes to the o2 harness and i believe it to be the low oil level light so i removed this. correct me if i am wrong.

tan w/ lt green stripe
this wire goes to the test plug and then to pin 22.

red w/ wht stripe
this is for the coolant temp guage and i can hook that up

wht w/ red stripe
this is for the oil pres guage i believe or is it the oil pressure light? either way correct me if im wrong please.


GREY CONNECTOR

red w/ green stripe
this wire has two parts, one comes from the grey connector and one comes from the coil. they both splice together and then continue as two wires. one wire to the TFI connector then the other to the eec relay.

red w/ blue stripe
this wire goes to the TFI connector.

wht w/ pink stripe
this wire goes to o2 harness then nothing like the other 2. can i remove this?

tan w/ yellow stripe
this wire goes to three places from the connector. it goes to a t where it branches off into 3 wires. one wire goes to the coil, another wire goes to the TFI connector, and the last one goes through a 22 kohms resistor then to pin 4 on the eec.

if someone coudl fill me in as to what all these wires need to be connected to and what ones i can get rid of that would help IMENSELY. I already have all of the emitions garbage removed correctly i jsut dont know out of these wires what needs power and when.

another issue i have is with the fuel pump. how do i go about installing a fuel pump relay. the 90s have the fp relay on the underdash harness not in the engien bay liek the other late model harnesses. if someone could give me some advice on that also i woudl GREATLY appreciate it.

THANKS,
Tom
 
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Give this a try...

This might help you out. I don't know if all the info you need is there but while skimming through it I think alot if not all of the wires you need for the fuel pump relay are the spare wires you have. It's in MDI format...sorry it's all I can get...you are going to need Microsoft Document Imaging to view. Hope it helps.



http://4bs.bravehost.com/Electronic Engine Control (5.0L) (Grid 12-15).MDI
 
BLACK CONNECTOR

blue w/ yellow stripe
wire goes to the o2 harness plug then nothing meaning there is nothign on the 02 harness to plug into. can i jsut remove this wire?


grey w/ red stripe
this wire goes to pin 46 on the eec

This wire is for the neutral safety switchThe computer wants to make sure the A/C is off due to
the added load on the engine for the engine running tests. It also checks to see that the
transmission is in Neutral and the clutch depressed (T5, T56, Tremec 3550 & TKO)). This prevents
the car from being driven while the computer is in test mode. Key On Engine Running test mode
takes the throttle control away from the driver for several tests. This could prove hazardous if
the computer was jumpered into test mode and then driven.

wht w/ purple stripe
this wire goes to the o2 harness and i believe it to be the low oil level light so i removed this. correct me if i am wrong.

Looks like you are correct on this one

tan w/ lt green stripe
this wire goes to the test plug and then to pin 22.

This wire is the fuel pump relay trigger. The computer switches this wire to ground to turn the fuel pump on and off.


harness03.gif


Neutral safety switch and backup light switch:
attachment.php
 

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  • Neutral safety & backup switch wiring..GIF
    Neutral safety & backup switch wiring..GIF
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