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P0300 code. Came up checked for spark troubles found nothing good spark good compression something is making the vehicle sound rough should I suspect a weak fuel pump anyone have a common fix

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Borrowed from OBD
"Basically this means that the the car's computer has detected that not all of the engine's cylinders are firing properly.
A P0300 diagnostic code indicates a random or multiple misfire. If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A P0302 code, for example, would tell you cylinder number two is misfiring. Unfortunately, a P0300 doesn't tell you specifically which cylinder(s) is/are mis-firing, nor why.


  • the engine may be harder to start
  • the engine may stumble / stumble, and/or hesitate
  • other symptoms may also be present
  • code P0300 may mean that one or more of the following has happened:
    • Faulty spark plugs or wires
    • Faulty coil (pack)
    • Faulty oxygen sensor(s)
    • Faulty fuel injector(s)
    • Burned exhaust valve
    • Faulty catalytic converter(s)
    • Stuck/blocked/leaking EGR valve / passages
    • Faulty camshaft position sensor
    • Defective computer"

  • StarI suggest you start simple.... replace the plugs and test the spark plug wires. Make sure all connections are tight.

    Posted on Apr 02, 2015


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    Ive changed almost every component on my car that may not make it want to fire off, im not getting any fire to my 1 plug i have changed my coils as well as the module the only thing i havent done is...

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