I'd be more inclined to think yours is an oil control problem, and not an ignition problem. Perhaps valves, guides, or seals (who knows - maybe even rings?!). But I'm not all that familiar with the idiosyncracies of the V6 in your car, so maybe some of the experts here can speak up. If I'm not mistaken, I believe that V6 did tend to have oil control issues with the rings.

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