How to test a coil?

Discussion in 'Fox 5.0 Mustang Tech' started by BlackFox5.0, Jun 11, 2003.


  1. BlackFox5.0

    BlackFox5.0 Founding Member

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    i found a coil i might be able to use, i wantto see if it will make more spark than mine now.... how do i test it to see if it's better?
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  2. speeddemon40

    speeddemon40 Founding Member

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    WHAT KIND IS IT?? IS YOURS STOCK?
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  3. BlackFox5.0

    BlackFox5.0 Founding Member

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    yep, and i have another stock one, i think it's from a ford truck.....but they look the same
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  4. carbed 85 gt

    carbed 85 gt New Member

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    Dude why mess with a stock truck coil:confused: Buy a MSD or Accel or Mallory for 30 to 45 bucks. Get about 10000 to 15000 more volts very cheap , any way a truck coil probably wont make a better spark.:D
    #4
  5. BlackFox5.0

    BlackFox5.0 Founding Member

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    because i don't have any money to spend :(

    i think my coil might be going bad, i don't know for sure, i just wanted to rule out the possiblity that it is bad...

    i was thinking about an Accel or FMS piece, don't know yet.....
    #5
  6. cjones

    cjones Founding Member

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    to test the coil;

    get an Ohm meter and

    check primary resistance between Pos and Neg terminals on the coil
    resistance should be 0.3 - 1.0 ohms

    check secondary resistance between Pos term and coil wire terminal
    resistance should be 8000 - 11500 ohms

    repeat secondary resistance test between Neg terminal and coil wire terminal
    resistance should be 8000 - 11500 ohms

    check resistance to each terminal and gound(coil case)
    resistance should be infinite
    #6
  7. blkstangman88

    blkstangman88 New Member

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    easy way to test a coil, using a extra spark plug, gap it right, and plug it into a spark plug wire and place it on ur uper intake. when u turn the car over (dont start it) the spark should be blue, NOT WHITE, if its white, the coil or distribitor is bad. if the spark is blue, then the coil is still good. the blue spark is much hotter, thats why i say it must be blue. a pro mustang mech told me this and this is how i found out my stock coil was bad.
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