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1998 Mercury Grand Marquis GS runs Rough when cold

When I start my 1998 Mercury Grand Marquis from a cold start (it has a 4.6L V8 in it) it runs really rough and spits and studders until it warmes up and gets really bad mileage (8-10 MPG), Ive ran injector cleaner through it, replaced the spark plugs, swapped out coil packs in it,Cleaned the EGR Valve and replaced the fuel filter with no luck, Any ideas?


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I have the same problem and can
Not figure it out did u have any luck?

Posted on Oct 17, 2011

  • hendershottb
    hendershottb Jan 16, 2013

    idk if this would help but yesterday my mecanic loosened up my distributer and turned it a little bit and it it fired right up then we timed it right its been doin doin good ever since but one of my spark plug wires was switched around and had two replace one of the wires



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