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Msd 6al2 Install Question!!

  • Thread starter Thread starter Wonderbread750
  • Start date Start date May 16, 2014
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Wonderbread750

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Apr 24, 2014
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May 16, 2014
#1
  • May 16, 2014
  • #1
I got all the wires ran correctly on the car except the gray tach wire, i wired it to the freen and yellow striped wire and i lose all spark, but when removed car sparks, what color wire is the correct one?
 

mikestang63

SN Certified Technician
Aug 27, 2012
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May 16, 2014
#2
  • May 16, 2014
  • #2
And low and behold


 
Last edited: May 16, 2014
Reactions: jrichker
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Wonderbread750

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Apr 24, 2014
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May 16, 2014
#3
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  • #3
But what is the tach output wire on the mustang?
 

Onefine88

Previously 89SSC18
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May 17, 2014
#4
  • May 17, 2014
  • #4
I may be wrong about this because its been awhile since I wired one of these. But, I'm pretty sure that if you use the TFI wiring harness you do not need to use the tach output wire.
 
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jrichker

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May 17, 2014
#5
  • May 17, 2014
  • #5
Onefine88 said:
I may be wrong about this because its been awhile since I wired one of these. But, I'm pretty sure that if you use the TFI wiring harness you do not need to use the tach output wire.
Click to expand...
Right on target for use with the stock tach.!
The TFI module dark green/yellow wire feeds the stock tach and the computer. Make sure it is connected just like the stock setup.

Only aftermarket tachs use the MSD tach connection.

Diagrams courtesy of Tmoss & Stang&2birds

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs


Fuel, alternator, A/C and ignition wiring


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

O2 sensor wiring harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangO2Harness.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pin out
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif

Visual comparison of the Ford Fuel Injectors, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/Ford_Injector_Guide.jpg
 
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