Question about 1991 Mercury Grand Marquis

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Loss of power when up to temperature

I have a low mileage (56,000) car with a 302ci that lately drops in power and misses when up to temperature. It runs fine when first misses or stumbling but as it warms up it runs poorly. any help would be much appreciated.!! Thanx ....Dan

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  • 1216bandit Nov 03, 2008

    Thanx, I will give that a whirl. Just wondering though, if the wires are the problem would the car still start and run OK till temp builds up?

  • 1216bandit Nov 03, 2008

    sprayed the wires while the engine was not yet up to temp and it ran missing. any other thoughts? Thanx...Dan



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Sounds like a spark plug wire issue, spray the wires with a fine mist of water and see if it misses.

Posted on Nov 03, 2008

  • yadayada
    yadayada Nov 03, 2008

    Yes, these kinds of problems are most apparent hot under load, like passing or pulling a hill. Remember all conducters work better cold, no matter what they are, house wiring or spark plug wires.

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