Engine missing and check engine light flashes

Discussion in 'KJ General Discussion' started by bmw2rdr, May 8, 2019.

  1. bmw2rdr

    bmw2rdr New Member

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    My 2004 Jeep Liberty has 213K miles and other than replacing normal wear items has been extremely reliable. On routine start the engine started missing as if only 2-3 cylinders were firing and the check engine light started flashing. Running too poorly to drive so I called a wrecker for towing to garage. Mechanic said scanner showed multiple misfiring and advised the computer was probably faulty. He replaced the computer and said running was improved but misfiring continued with multiple codes showing. He has had the Jeep for a week and still has been unable to fix or find the problem. Suggestions please.
     
  2. Billwill

    Billwill Full Access Member

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    Your Mechanic should have been able to pull the codes out with reference to the misfires. With those codes in hand you can chase up the problem ie. if it is only certain cylinders misfiring you can swap over injectors or plug modules.

    If it is all over the place then could be the CAM or Crank sensor or a mechanical problem.

    Post those CEL codes and you will get some good advice here.
     
  3. J33Pfan

    J33Pfan Full Access Member

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    Go back to basics.
    check spark plugs for rich or lean etc.
    Use the Copper plugs listed on the Hood.
    check compression
    check fuel pressure
    check for vacuum leaks. PCV, Hoses, etc
    is your fuel good?

    plus what was already mentioned here.
     
  4. JasonJ

    JasonJ Full Access Member

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    These are all things your mechanic should have already looked into, probably multiple times.... if he hasn't, pay him his bill and move the vehicle to a good automotive technician... someone with more training that how to change a tire.

    So many mechanics are in over their heads with any vehicle newer than the early 2000s, they go right to blaming "the computer"... "the brain" as they call it. What they don't realize is just how rare that the main PCM goes bad, and that these vehicles often have about a dozen computer modules operating the vehicle functions.
     
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  5. mrlavalamp

    mrlavalamp Full Access Member

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    Nail on the head JasonJ.

    A good mechanic this is not.
     
  6. dillon

    dillon New Member

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    Yep, just because they are paid to be a tech doesn't mean they are a tech. unfortunately....
     
  7. J33Pfan

    J33Pfan Full Access Member

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    First they change the computer next "oh You need a New Engine"
    but before they change the engine they bill ya for a tuneup & oil change on the old one!
     
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