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Discussion Starter #1
Hey all, I've had an ongoing issue where the plug wires and ignition coil will start to arc between each other (you can clearly hear the electrical tick and engine gets rough with it does tick.). I have replaced the plug wires (not cheapo wires, but aftermarket ones) and it seemed to fix it for a few days, but on cold starts, it does it again. The issue goes away after 10 miles or so of driving. The car loses a lot of power and acts like it wants to stall even at a higher rpm. Plus I get a cylinder 1 misfire code. It is only the first cylinder. My next step is to replace the ignition coil. But maybe its a grounding issue? I haven't messed with the coils apart from unplugging it to do valve cover gaskets and replace plugs/plug wires. Let me hear what you all think, thanks!

As a side note. I did run into this issue very briefly, one or two occurrences, before I changed anything like the plugs/wires, gaskets.
 

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in dire need of an organic chemistry lesson
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How old are the coils? Exchange the coil #1 with the coil from another cylinder and see if you still get misfier. If you ever decide to replace coil packs I recommend to replace all of them.
 

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Discussion Starter #3
How old are the coils? Exchange the coil #1 with the coil from another cylinder and see if you still get misfier. If you ever decide to replace coil packs I recommend to replace all of them.
Factory coils. The 2.8L has a single piece coil pack so there's no way to swap, thus replacing it would mean it replaces all anyways.
 

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It's been a while since I've looked at a V6 coil, but the (high voltage) grounding will be via a screw (probably) directly to the metal of the engine, i.e. not via a wire. So check that the mounting surface is clean and screws tight. Same goes for any connection between the metal the coil pack mounts to and the metal the plugs are screwed in to--that forms the return path for the spark current.

If the coil pack is dirty, e.g. oily film, you might get electrical tracking from one plug connection to another. You could clean it with a gentle degreaser. MAF cleaner would probably be ok, for example, but I wouldn't use brake clean (which seems to be a solvent for everything).
 

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Factory coils. The 2.8L has a single piece coil pack so there's no way to swap, thus replacing it would mean it replaces all anyways.
aaaarrrrggghhhh, this damn V6 again. I hate it :LOL:
 

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This is almost certainly not a problem with the coil pack.
You say it arcs, how do you know it arcs ?
Most likely a faulty plug or contamination of the plug porcelain or cap.
Also could be a bad injector.
Could be low compression in cylinder 1, what are the compressions ?
 

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Discussion Starter #8
This is almost certainly not a problem with the coil pack.
You say it arcs, how do you know it arcs ?
Most likely a faulty plug or contamination of the plug porcelain or cap.
Also could be a bad injector.
Could be low compression in cylinder 1, what are the compressions ?
I know its arcing because you can hear the electrical shocking sounds in time with when the plug wire is given power. And I found out the unpleasant way by being shocked when poking around. That specific arc was between the coil pack and spark plug wire socket. And like I said before, I ran into this issue on the previous plugs/plug wires but only briefly. The coil pack is the only piece that hasn't been replaced. I do not have the means to check compression. Doubtful its the injector since the car only runs rough when its arcing.
 

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Discussion Starter #9
Pretty quick update for those curious, I saw a video where they lightly threw some water over the plug wires and coils so see if that would promote arcing. Lo behold it showed an arc between the 1st cylinder coil and the coil mount. Pretty noticeable one too. So I've already got a new coil pack on the way and hopefully that'll solve the issue. Heres a quick video of the sparking:
 

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The spark will take the easiest path, which should be the spark plug electrodes. If even one of the two plugs connected to the arcing coil is defective (burned-away electrode for instance) then the firing voltage may be so high that the next best place is right from the coil to ground. This is hard on the coils, which will develop an excessively high Voltage and can break down the internal insulation. I tend to doubt a new coil set solves this problem, unless it is already damaged intermally. Try using an Ohm meter to check the resistance through each coil's secondary (between the opposite plug wire terminals). Any with extreme resistance would mean there is a break that is arcing inside the coil.

Assuming that they check out OK, I would clean those coils with sudsy water and rinse with distilled water, then replace the plugs.
 

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That is definitely the problem.
There is a crack or a hole burnt in the coil pack, where it is arcing.
This could be repaired.

As ylwagon suggested, this might have a faulty plug/s.
I suggest you check the spark plugs and replace if old or deteriorated, BEFORE repairing or replacing the coil pack.
Faulty plugs could have caused this problem. iirc plug gap 1.6mm
 

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Discussion Starter #12
That is definitely the problem.
There is a crack or a hole burnt in the coil pack, where it is arcing.
This could be repaired.

As ylwagon suggested, this might have a faulty plug/s.
I suggest you check the spark plugs and replace if old or deteriorated, BEFORE repairing or replacing the coil pack.
Faulty plugs could have caused this problem. iirc plug gap 1.6mm
I've already ordered an extra plug to put in since I figured it would be fouled anyways due to the misfires. And I got a half-decent deal on a coil pack, so might as well take any worry away from future issues. I did make sure the plugs were gapped to spec from the Haynes manual which also gives 1.6mm.
 

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I've already ordered an extra plug to put in since I figured it would be fouled anyways due to the misfires. And I got a half-decent deal on a coil pack, so might as well take any worry away from future issues. I did make sure the plugs were gapped to spec from the Haynes manual which also gives 1.6mm.
I'd tend not to replace a single plug, generally - unless the others were very new. There are also many tales of defective or rapidly failing aftermarket V6 coil packs; so what did you buy?
 

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Discussion Starter #14 (Edited)
I'd tend not to replace a single plug, generally - unless the others were very new. There are also many tales of defective or rapidly failing aftermarket V6 coil packs; so what did you buy?
Plugs were replaced within the last 500 miles so a new one shouldn't throw anything off. I bought a Standard Motor Products (not parts) coil pack. The same company that my plug wires are from. It runs around 70 on rock auto but I found the same one on Amazon for 50 shipped.

I could have bought a Hitachi one for 30. :LOL:
 

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Replacing just the one plug should be fine.
I don't know anything against the coil pack that you bought, but I would have gone with the Hitachi.
I suggest you hang on to the original, just in case.
 

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Standard Motor Products brand (I think that is what Tipd14 meant) is what many independent shops use for aftermarket replacement for various parts on most vehicles.
Standard Motor Products - Wikipedia
Yes, it's a wiki, but it gives a little background on the company itself.
 
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