02 Lincoln LS Misfire

Discussion in 'Domestics' started by afresta, Feb 1, 2012.

  1. afresta

    afresta Newbie

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    02 Lincoln LS
    V8 4. 9 L
    Misfire, No Check Engine Light on
    Hooked up scanner no codes. Replaced plugs on all cylinders and is better but still think I have a bad coil. Why would the check engine light not be on if it's supposed to detect misfires.
    Even pulled of electrical connector to a coil while running and still no code or light
     
  2. kev2

    kev2 wrench

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    first does the CEL come on at start @3seconds then go out?
    You have a scanner did you ck pending and while there history?
    you are sure the scanner communicated ?

    answer that and tell if you have a scanner OR a code reader we can look at more items with scanner that may pin it down ie closed loop, ECT, STFT, counters etc
     
  3. afresta

    afresta Newbie

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    Hi
    I have a snapon scanner
    The cel comes on for 3 sec then goes off
    No codes in history or present
     
  4. NickD

    NickD wrench

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    With a misfire, I always to a compression check first. If that is good, use a spark gap tester with an old fashion vibrator to drive the coils, if that is good, check the trigger voltages, if that is good, check out the injectors.

    Then I ask myself, why did I ever sell my fully restored Model A, should have used it as a daily driver, real easy to work on. And certainly no problem keeping up with traffic since they are lowering the speed limits every five minutes, with Homeland Security cops on every street corner.

    Recall reading all those 50's science and mechanics magazines, by 2000 we will be driving at 400 mph. They sure missed the boat on that, 4 mph is more like it.
     
  5. kev2

    kev2 wrench

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    pulling the coil wire for a short time may not set DTC- we would need to get the parameters for setting code - ECT, TPs, - TIME come to mind...

    But that is manly academic ... how did all the old plugs look anything there to help ID a hole to ck on?
    As all the diagnostics are not helping we go to basics- check plugs, compresion test, vac test, coil output use a plug tester, injector - flashing? aand will need to see if actually spraying...
     

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