[1995 3.8] Which Coil Wire Is The Negative?

98Mustang2017

Active Member
May 3, 2017
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Tried search and nothing.
there's 3 yellow wires and a red. The yellow's may have a stripe color code, i'll have to get a better look.

Thanks.
 
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wmburns

SN Certified Technician
Aug 14, 2009
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Houston Texas
Let me see if I can help you answer your own question with some information pointing in the right direction.

The ignition system like many modern cars is on a "ground start" circuit. That means that the positive is "always on" and that the circuit is completed by the PCM grounding the signal return line inside the PCM.

Sooooooooo by that logic the RED wire is positive. And the yellow wires are the negative signal return line for each primary side coil pack cylinder pair.
 
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98Mustang2017

Active Member
May 3, 2017
155
15
38
ct
Let me see if I can help you answer your own question with some information pointing in the right direction.

The ignition system like many modern cars is on a "ground start" circuit. That means that the positive is "always on" and that the circuit is completed by the PCM grounding the signal return line inside the PCM.

Sooooooooo by that logic the RED wire is positive. And the yellow wires are the negative signal return line for each primary side coil pack cylinder pair.
Don't think i forgot about you, Burnsy !
I know i didn't reply when you helped me out, But i Saw !
I've been doing other car things that were more important at the time but i can almost do the flame thrower. Just need to wire, relay, bung, and switch.

Just did some bench testing with a coil i got for $8 on ebay back in January when you helped me out:
sparkk.png


I still need to side-pipe the exhaust from the turbocharger. (mid-rear -passenger side. front of tire.)
Aaand finish my brake system upgrades;Hydraulic rear handbrake. Dual piston front brakes.