Mk viii #3 coil keeps blowing

Lincoln Mark VIII

  1. BlackCloud

    BlackCloud LVC Member

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    1998 mark viii lsc, the #3 cylinder ignition coil blows out every time the engine is revved high. Any ideas as to the problem? Went through 3 ignition coils so far.
     
  2. slowmkviii

    slowmkviii Dedicated LVC Member

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    Oil on it?
     
  3. BlackCloud

    BlackCloud LVC Member

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    No oil. No water, dirt, or contaminents. Wires look good, but after that I'm usually at a loss with electrical stuff.
     
  4. unity

    unity Dedicated LVC Member

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    Very odd. The coil is alway hot until grounded if I recall. And its only 12v that is grounded by the ECU. To have a specific coil go bad could indicate an ECU issue or you are using aftermarket coils. Only go OEM. I would take a used OEM over a new aftermarket any day. With all that said, I can not see how its RPM related, even more strange.
     
  5. BlackCloud

    BlackCloud LVC Member

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    Both aftermarket and OEM coils blow. ECU... that's an idea. I'm thinking maybe the wires where I can't see them or some sort of module, but have no idea what. Maybe I'll see about replacing the wires and see what happens.
     
  6. unity

    unity Dedicated LVC Member

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    You could disconnect the ECU and test the wires. I would not do so with the ECU connected. The coils are in pairs, which is even the stranger part since you have an issue with one and not two. Two coils alway fire at the same time, hence the "wasted" spark system. Its for emissions.

    edit: Oh, crazy thought but maybe replace its companion coil. Maybe the companion is the actual issue. Just a wild guess but at this point...

    As for companions, I think the order is:
    1&6
    3&5
    4&7
    2&8

    But I would verify that.
     
  7. cadikiller

    cadikiller LVC Member

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    Might be stupid question. Did you check the plug? Screenshot_20171113-174539.png Just throwing out ideas out hear but could the ressistance of the path through plug be to high. Google seems to indicate this is the most common cause of coil failure. Never ran into it myself just the first thing that popped into my head.
     
  8. BlackCloud

    BlackCloud LVC Member

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    Plugs are new, with the correct gap. No visible problems with the wires, but I don't have my volt ohm meter handy. Couldn't be the stainless steel connectors I used to replace the rusty spring connectors, either, the problem started first, which is what led me to start replacing them... its just weird. Maybe other coils would blow too, if given the chance, but I back off the throttle as soon as it happens. There's supposed to be a good auto electrical place in Louisville, but lost the address. I'll probably seek them out as soon as I'm done with the suspension...
     

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