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Had a misfire over three days last week only when she got warm.
By powers of deduction, came to the conclusion that it was number two cylinders coil pack.

Bearing in mind she's only done 49k and I put ngk platinum plugs in a few years ago.

When I took number two plug out she was a little pitted in the firing area but was quite rusty around the external socket flats?? Mmmmm! I thought.

Ordered a new coil pack off ebay which I fitted on Sunday and had alreadt fitted some more new ngk's. My oh my what a difference in performance. I just cannot believe how quickly she now picks up.

My theory is that this coil pack, although no misfiring or hesitation could be felt until last week, had been running at poor capacity for a very long time indeed. It is my only theory for the external metal of the plug to rust up as there's been no water getting in there.

I would advise you all to carry out a thourough plug inspection purely on the grounds of what my findings have been. Honestly, its as though 20 to 30 hp has been thrown at her. There is a phenominal difference.
 

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Dummy alert! What exactly is a coil pack? I found them on eBay but although they are called packs, they're sold individually?? And how many does my v6 have? And are they front or back of the engine?
 

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traditionally you have a single coil which is triggered 4 times every 2 turns of the crank, to produce the HT which is distributed to each plug in turn via the rotor arm and dizzy cap. This is inefficient especially on high revving engines, with long lengths of HT cable and more critical components that if slightly under par affect the whole engine.
With coil packs you have 1 coil per spark plug, the LT trigger to each coil is done by the ECU, the coils are much nearer the plugs with short HT cable lengths, the end result is a fatter spark which is more precisely controlled and timed, giving better combustion and efficiency etc.
Someone who is good on electrics might be able to expand on this.
 
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