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Old 07-25-2011, 04:52 PM   #1
BowerR64
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How do the coil packs function?

I took mine off to clean them, there was a post i read some time back and some one took the coil packs apart and used dialectric grease after he cleaned them up.

Now that i have them out i dont quite understand how they work. I know how an older coil works on an engine with a distributor.

These coil packs im not quite sure about. I see a 2 pin plug which i think is + and -? or is it + and a signal? or 2 alternating + leads?

The part i question is the sleve on the tab that has the bolt running threw it. The color of it makes me thing its used as a ground?



The bolts even look as if they are designed to ground. I just want to make sure i get everything making good connections as they should be. If its just a spacer so the bolt isnt over tightened why use brass? or copper and not use a cheap cast sleve?


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Old 07-25-2011, 05:23 PM   #2
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The metal sleeve is in there to keep you from breaking the plastic by over-torquing.

Of course, the coils work like old coils, but I'm not sure you understand exactly how those work. Let's go back to the old points system because it might be a bit easier to understand. The coil is fed with a constant hot, and that hot is grounded on the other side of the coil under non-firing operation. When I wrote "the other side of the coil" I meant electrically, the coil windings are grounded on the opposite side of the hot. The points hold the ground in place to discharge the coil. When the points open, the high voltage charge induced by the coil finds the path of least resistance- which is the spark plug gap, and the only other path it has to take. That's your spark at the spark plug.

No coil is going to be permanently grounded, or it wouldn't work. There's no need for a safety ground on the outside of the coil because it's plastic.

Perhaps you're confusing an inductive coil with an AC transformer. DC can't be transformed from low voltage to high voltage, but it can be resisted to reduce voltage. Inductive coils create a high voltage charge, but there's no transformation of current, and the current is reduced to nearly nothing. In other words, an AC transformer can carry a load, but a DC inductive coil can't. If you've ever had a spark plug get damaged physically so that the center conductor touches the back strap then you know you just fried the coil because without resistance the current would go through the roof and melt the varnish on the coil windings.

On these coils, the computer's ignition module breaks the ground connection to the coil so it will fire.
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Old 07-25-2011, 11:23 PM   #3
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I thought maybe they had a secondary coil maybe for open loop or somthing.

Ground, coil 1 on connector, then coil 2 on connector then out to the spark plug.

Or maybe one side measured the condition of the coil by the ECU with some emitions sensor or some crap.
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Old 07-26-2011, 05:36 AM   #4
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Nope, the coil builds a charge, then that charge is released when the coil looses it's ground. All that happens in a millisecond.

What would be really nice is if we had one bank 1 O2 sensor per cylinder, and spark could be adapted with that information. Adapted meaning multiple sparks or less sparks if the sensor detected rich or lean conditions.
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