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anyone know how ignitions work?

  • Thread starter Thread starter OonDeanisS
  • Start date Start date Jan 9, 2007
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OonDeanisS

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Jan 24, 2007
#61
  • Jan 24, 2007
  • #61
seijirou said:
YEs because red/blue is hot in start. red/green is hot in run. Normally the tfi module provides the power to the coil when the key is in the start position. If you do not have a TFI module, you will not have this function, and thus you have your problem.

What you need to do, is connect your coil to both red/blue and red/green wires.

-HOWEVER-

You also need to put a diode on each wire so that power from one isn't going to blackflow into the other circuit. Otherwise turning the key to ON will be like turning it to START and ON at the same time.
Click to expand...

So attaching r/b and r/g to the small red wire will do the trick as long as i have a diode on both of them? how does a diode work?

thanks for all the help, how old are you guys? im 20
 

OonDeanisS

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#62
  • Jan 24, 2007
  • #62
and what kind of diode should i use? i've never used one before.
 
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seijirou

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#63
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A diode is a one-way check valve for electrical current. It only allows power to flow one way. It goes in-line with the wire. Wire it to allow current to flow to the coil, but not from it. I'm 25
 

OonDeanisS

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#64
  • Jan 24, 2007
  • #64
sounds good, i just got it started!! but i did it with no power in start, just the red wire attached to my fuel pump toggle switch. So now can i just attach a new wire from the white/pink with a diode on just that?
 
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seijirou

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#65
  • Jan 24, 2007
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Well the fuel pump needs to have power in both cases too, so using that power will work.
 

OonDeanisS

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#66
  • Jan 24, 2007
  • #66
but my fuel pump loses power in start too and i dont know why so should i just get a wire from the w/p to the fuel pump with a diode on it? what kind of diode do i need?
 
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seijirou

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#67
  • Jan 24, 2007
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Damn dude your wiring is ghetto fabulous.
Just go to radio shack and tell them you need a diode for low current automotive applications. They'll hook you up.
 

jrichker

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#68
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  • #68
The fuel pump should be relay controlled.


EDIT: Relay & socket part numbers
Relay Radio Shack Catalog #: 275-226
Relay socket Catalog #: 55017871

Igniton wiring...
The red/green wire is hot in both crank and run modes, since it used to activate the EEC power relay.
It goes to the small red wire on the MSD box. The wire wire fro the MSD goes to the distributor (green/yellow
on the original wiring) The big read wire goes to a 20 amp inline fuse that connects to the battery side
of the starter solenoid. The big black wire goes to a bare metal ground on the body.




From the diagram...

Diagram courtesy of Tmoss & Stang&2birds


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/

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

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

Computer,. actuator & sensor wiring
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

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

Vacuum routing
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

By the way, I'm 61 - old enough to be your grandfather...
 

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OonDeanisS

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#69
  • Jan 24, 2007
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well i got it to work by attaching the small red to the red/lt grn under the ignition switch, and by attaching the white/pink wire in the engine bay (which somehow was only hot during run) to the red wire as well, and it doesnt start when i turn it to run, but starts right up like a normal car. yessss. Only problem now is the brand new battery is dead.
 

89streetbeast

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Jan 24, 2007
#70
  • Jan 24, 2007
  • #70
OonDeanisS said:
well i got it to work by attaching the small red to the red/lt grn under the ignition switch, and by attaching the white/pink wire in the engine bay (which somehow was only hot during run) to the red wire as well, and it doesnt start when i turn it to run, but starts right up like a normal car. yessss.Only problem now is the brand new battery is dead.
Click to expand...



glad to hear you got her running man. think i was confusing more than helping , but i tried. sounds like a big wiring fiasco you got there. a friend of mine had the same problems with his 89 when he went carbed, he ended up buying an hei dizzy so all he had was 1 wire to fiddle with.
 

OonDeanisS

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#71
  • Jan 24, 2007
  • #71
thats ok, it was worth all the confusion
 

OonDeanisS

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Jan 25, 2007
#72
  • Jan 25, 2007
  • #72
so the alternator only has the black and orange that turns into green and the white and black? i think the alternator is good because it stays running when i detach the battery, but its not charging the battery. is that green one the one that charges it?
 

jrichker

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#73
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There are two green wires in the alternator circuit.

One is the dark green fuse link wire that connects the alternator power feed to
the battery side of starter solenoid. If the fuse link blows, the alternator will not
provide power or charge the battery.

The other light green wire is the one that signals the voltage regulator to turn on
because the ignition switch is on and the engine is supposed to be running. If it
doesn't have 12 volts with the ignition switch in the run position, the alternator
will not charge. This same light green wire also operates the battery signal light
on the instrument panel.
 

OonDeanisS

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#74
  • Jan 28, 2007
  • #74
jrichker said:
There are two green wires in the alternator circuit.

One is the dark green fuse link wire that connects the alternator power feed to
the battery side of starter solenoid. If the fuse link blows, the alternator will not
provide power or charge the battery.

The other light green wire is the one that signals the voltage regulator to turn on
because the ignition switch is on and the engine is supposed to be running. If it
doesn't have 12 volts with the ignition switch in the run position, the alternator
will not charge. This same light green wire also operates the battery signal light
on the instrument panel.
Click to expand...

what do u mean by the alt. power feed? where is this fuse? and if it was that fuse that blew, wouldnt the car shut off when i detach the pos. side of the battery?

also, no 12v in run at the lt. grn wire means the alt. will not charge... [the battery?]

thanks
 

jrichker

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  • Jan 28, 2007
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OonDeanisS said:
what do u mean by the alt. power feed? where is this fuse? and if
it was that fuse that blew, wouldnt the car shut off when i detach the pos. side of the battery

also, no 12v in run at the lt. grn wire means the alt. will not charge... [the battery?]

thanks?
Click to expand...
I guess I must be speaking GEEK or something. I never thought that my
explanation was that hard to understand....
 

OonDeanisS

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#76
  • Jan 28, 2007
  • #76
well that really doesnt clarify it much. can someone else please explain to me what jrichker said?
 
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seijirou

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Jan 29, 2007
#77
  • Jan 29, 2007
  • #77
OonDeanisS said:
what do u mean by the alt. power feed? where is this fuse? and if it was that fuse that blew, wouldnt the car shut off when i detach the pos. side of the battery?

also, no 12v in run at the lt. grn wire means the alt. will not charge... [the battery?]

thanks
Click to expand...

Unless you can think of something else on your car that can take a charge, yes, it's the battery.

The altrernator feeds power to your car. It uses a wire to do this. The power feed wire. It's the thicker wires that come off the alternator. Just before it reaches the battery side of the starter solenoid, it goes through a fuseable link. All a fuseable link is, is a thinner piece of wire than the rest of the wire it's connected to.

If your alternator is not putting out any power, yes your car will shut off when you remove the positive battery cable. However, even if the alternator is putting out only 9 volts the car will still run. So it's not really a test of a good or bad alternator.
 

OonDeanisS

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#78
  • Jan 29, 2007
  • #78
oh, thanks. Whats the point of a fusable link? Sounds like i should have my alternator tested.
 
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seijirou

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#79
  • Jan 30, 2007
  • #79
OonDeanisS said:
oh, thanks. Whats the point of a fusable link? Sounds like i should have my alternator tested.
Click to expand...

It has the same point as a fuse. Just a different method. Most would agree it's a very much less effective method.
I agree, get it tested.
 

OonDeanisS

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#80
  • Jan 30, 2007
  • #80
so if theres too much current flowing through the little "fusable link" it will just snap?
 
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