Duraspark 2 wiring

Discussion in 'Ranchero Tech Help' started by Make, Sep 11, 2020.

  1. Make

    Make In First Gear

    Messages:
    4
    Hei

    I hope you understand my "Google Translate English".

    My car is a -79 Ford Ranchero GT

    I have installed the new wiring in the engine room of my car, and also I bought this ignition wiring harness. https://www.americanautowire.com/shop/ford-duraspark-ignition-harness, which is a little weird.

    In the wiring harness, the white and brown wires go to the same connector there ” To 2 way ignition module connector”

    If I connect that wiring harness while it is in the manual, then the Ignition Control Module will get 12 V from the red wire and approx. 9 V from the brown wire through the ignition coil while the engine is running !

    Should that brown wire between the Ignition Control Module and the ignition coil be cut off ?

    In my car, before no voltage has been applied to that white wire in the Ignition Control Module other than when starting the engine.

    Will that Ignition Control Module break if I install it according to the wiring harness instructions, or does it still work normally ?
     
  2. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

    Messages:
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    Location:
    Seguin, TX
    The Duraspark receives 12 volts during starting, and 9 volts during running. This helps prevent overheating of the ignition parts during running.
     
  3. burninbush

    burninbush In Maximum Overdrive

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    Location:
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    I'm worried about that 12v getting distributed to other places in the system?? Sounds to me like he wants to hook them together?? Depending on where he found the 12v, that would also seem to run the coil off 12v no matter how Ford intended it to go. He might need to recover the 9v (resistor wire) in the original wiring to run what Ford planned for it.

    To the post originator ... the 9v line was the result of a length of resistor wire that was folded-up inside the under-dash harness. If you need to fake it, try running a 1-ohm resistor in place of the long wire.
     
  4. Make

    Make In First Gear

    Messages:
    4
    So that was originally the case.

    As you can see, the Ignition Control Module white wire only when the engine is started becomes 12 V, when the car is running there will be no voltage at all.

    [​IMG]

    This is that finished wiring harness I bought.

    [​IMG]

    I understand that the ignition coil and Ignition Control Module white wire need 12 V when the engine is started and when the engine is running the ignition coil voltage drops to about 9 V.

    But with a connection like that, where the Ignition Coil + and Ignition Control Module white wire are in direct contact with that brown wire has such consequences that:

    When the engine is running, Ignition Control Module red wire get 12 V OK, but Ignition Control Module white wire get 9 V from ignition coil ???

    Should the brown wire be cut between the ignition coil and the Ignition Control Module so that the Ignition Control Module does not receive it at 9 V white wire when the engine is running?
     
  5. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

    Messages:
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    Location:
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    Oh, I see what you're asking-- when the module receives the 12 volts on the white wire, the module automatically retards the timing during engine start, to make it easier to start, especially when the engine is cold. Then, when the key turns back to run, the 12 volts comes in on the red wire, so the module reverts to normal timing control.
     
  6. Make

    Make In First Gear

    Messages:
    4
    Well I do not know why there Ignition Control Module has two voltage supply, probably just because like you said.

    But so if I install that wiring harness, when I return the ignition key to the run position from the start position, then the red wire in the ignition control module is 12 V and the white wire in the ignition control module is the same amount as in the ignition coil because they are together on that brown wire, so they both have about 9 V.

    Originally, that white wire has 0 V when the ignition key is in the run position. Ignition control module white wire and Ignition coil are not originally connected.
     
  7. Make

    Make In First Gear

    Messages:
    4
    Duraspark 2 is apparently a 45 year old Ford electronic ignition system.

    Does anyone have a Ford Duraspark Ignition Harness made by American Autowire in their car?
     

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