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EFI guru's help- CFI to EFI swap

  • Thread starter Thread starter jmood62
  • Start date Start date Oct 31, 2007
J

jmood62

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Oct 4, 2007
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Oct 31, 2007
#1
  • Oct 31, 2007
  • #1
search turned up nothing.......swapping a 85 auto to 5.0 EFI, 5-speed.. I already have, motor (vortech SC trim), trans, injector harness, 89 EFI mass air harness with A9L computer, 255l intake pump, and a new O2 sensor harness coming in the mail. Question is, will my dash harness run this, or do I need a 86 harness, or other ideas, comments????? thanks
 

samickguy15

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Sep 1, 2005
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Oct 31, 2007
#2
  • Oct 31, 2007
  • #2
You should be fine. There are very few wires which go to the dash. Just comb through your wiring diagrams and figure out which ones you need. I suspect you'll have the option of either running seperate wires or swapping connectors on one side or the other. Should be simple though since you've got both harness's to work with.
 
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jmood62

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#3
  • Oct 31, 2007
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just the gauges going to the dash? I noticed that the original dash/headlight harness has a coil plug, and so does the 89 mass air harness!, which one needs to be used? also, the starter solenoid used to be on the passenger side, just move it to the drivers? and just buy an alternator pigtail? it seems like the stock alternator had an external regulator......I have a newer alternator already. thanks for your reply.......Justin
 
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brynfiv

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  • Oct 31, 2007
  • #4
5.0 h.o. efi wiring

Once you put main harness in place where it goes here is how you can splice in and hook it up in any vehicle.

Look for brown connector-should be located behind drivers strut tower in engine compartment. You need to set up the following.

Red/light blue - 12 volt crank only
white/purple - 12 volt crank only
Red/green - 12 volt crank and run
White/red - goes to oil pressure gauge
tan/yellow - Tach
Green/purple and purple/yellow are clutch saftey switch- open circuit allows starting. should run to your clutch switch and neutral switch on a T-5. Leave open with automatic.



Almost there - look for the green connector, it will be located inside the car right by the computer connection. You need to set up the following.

Gray/yellow - 12 volt run only
purple - 12 volt when air is on for fast idle
dark green/yellow - fuel pump control - to inertia switch then to fuel pump(really should run this through a relay)
pink/orange - speed sensor negative/ground
green/black - speed sensor positive
pink/green - check engine light
 
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jmood62

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Oct 31, 2007
#5
  • Oct 31, 2007
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you are the man.......One more thing....the brown connector, it will be on the mass air harness right? not the dash harness?? do you know what wires for water temp and volts? use coil plug with the main harness, not the 85 dash? leave the starter solenoid on the passenger side? do you know how to modify for the newer alternator? thanks for all your help.....I owe you beer.
 
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jmood62

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?
 
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brynfiv

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  • Nov 1, 2007
  • #7
jmood62 said:
you are the man.......One more thing....the brown connector, it will be on the mass air harness right? not the dash harness?? do you know what wires for water temp and volts? use coil plug with the main harness, not the 85 dash? leave the starter solenoid on the passenger side? do you know how to modify for the newer alternator? thanks for all your help.....I owe you beer.
Click to expand...


brown connector is on mass air or speed density computer/engine compartment harness. There is another connector by the brown one, can't remember which color it is, but red/white stripe in it is water temp gauge wire, white/red stripe is oil pressure gauge. You will probably have to use the 85 model sending units, not sure. Use coil plug on main harness, you're creating a stand alone efi wirng harness by wiring this way. move battery and solenoid to drivers side,induction will pretty much take it's place on passenger side. Voltage gauge is gonna come in with wiring up that 2-G alternator. it has an internal regulator. Google 2-G alternator and it wont be hard to find, sorry but it's been a while and I can't remember. If you were in alabama, I'd take you up on the beer. lol, later man.
 
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