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Ballast Resistor trouble

  • Thread starter Thread starter 5.0Mustang1984
  • Start date Start date Feb 22, 2006

5.0Mustang1984

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Feb 22, 2006
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Feb 22, 2006
#1
  • Feb 22, 2006
  • #1
I had trouble figuring out why I was having a weak spark, so i replaced all of my ignition parts to include the coil, ignition module, cap, rotor, wires, spark plugs, magnetic pickup, voltage regulator, and ignition switch, and still the same, i have a weak spark. so next i started to check all of the wiring, i tore it all apart and checked everything for a short somewhere, but couldn't find anything. so i shot the ballast resistor, and its supposed to be like .8 or 1.6 ohms, but mine is reading something crazy like 14 ohms. my question is, where is this ballast resistor located on my 84 gt? i tried to follow all of the wiring under the dash, but could not find it. what does it look like and could this high ohmage be giving me the weak spark? anything will help here thanks.
roger
 

jrichker

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#2
  • Feb 22, 2006
  • #2
AutoZone wiring diagrams

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model Mustangs
Here's the one for your car...

 

5.0Mustang1984

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Feb 24, 2006
#3
  • Feb 24, 2006
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Anyone else?
 

jrichker

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Feb 25, 2006
#4
  • Feb 25, 2006
  • #4
Yiu must have the duarspark system, which uses a ballast wire . Autozone's diagram for an 83 is next - notice the red/green resistance wire next to the block that says ignition.
 
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