Question about 1991 Ford F150

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Engine misses when placed under load

Engine runs fine while cold...once hot seems to misfire under load

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  • gjeffries Feb 19, 2009

    haven't done anything to engine since I recently acquired it...aws running fine and it started this miss under load...diagnostics indicate EGR valve or oxygen sensor... EGR valve is plugged off with no improvement....kick off OD and problem is less severe.

  • gjeffries Feb 19, 2009

    Thanks.

  • mike loshbough
    mike loshbough May 11, 2010

    when have you replaced plug wires

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Replace the plug wires this will fix your secondary ignition breakdown. the egr code is due to a bad dpfe sensor which is for back pressure on egr valve.this will not cause misfire.

Posted on Feb 19, 2009

  • mike loshbough
    mike loshbough Feb 19, 2009

    please rate this solution thanks

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