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P0300 random misfire

Discussion in 'Chevy Tahoe Forum (GMC Yukon, Cadillac Escalade)' started by loic, Sep 6, 2011.

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  1. loic

    loic New Member

    on my 99 tahoe 4wd ( about 150k miles), my engine light went on and got this code, also a couple weeks ago, it was saying bank 1 to rich..
    spark plug are only a couple months old.
    what could cause the misfire? ( before changing the plugs I also had the random misfire code show up then went away as I changed the plugs)
  2. 99'HEARTBEAT

    99'HEARTBEAT Moderator Staff Member Platinum Contributor 1000 Posts 100 Posts

    Trouble Code...P0300.....a Random Misfire, 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 EGR valve / passages
    • Faulty camshaft position sensor
    • Defective computer
    What Brand of Spark Plugs did you install??
  3. loic

    loic New Member

    I don't remember the brand, they may be bosh, ill have to look.
    I must say that I don't like your list.......
    I changed the o2 sensors a couple months ago.
    That truck has a throttle body spacer and magnaflow exaust (was like this when I bought it)
  4. 99'HEARTBEAT

    99'HEARTBEAT Moderator Staff Member Platinum Contributor 1000 Posts 100 Posts

    Regarding which Spark plugs you installed......The Vortec Engines Run And Perform Better when A/C Delco Plugs are installed, and the ones you want are the......A/C Delco Platinum Spark Plugs......with the Bosh plugs, that may be why you are getting a Random Misfire.
  5. loic

    loic New Member

    Easy enough, ill change them and see.
    Thanks.
  6. 99'HEARTBEAT

    99'HEARTBEAT Moderator Staff Member Platinum Contributor 1000 Posts 100 Posts

    I see you have a 99"......do you know if the Spark Plug Wires are the Original ones from the Factory??.....if so I would go with a New Set of Plug Wires.......
  7. loic

    loic New Member

    no, they dont look OEM, but some are kinda short that make some of the plug boot bent a little
  8. 99'HEARTBEAT

    99'HEARTBEAT Moderator Staff Member Platinum Contributor 1000 Posts 100 Posts

    From what you have just mentioned Regarding the Wires.....I would get a Correct set of Spark Plug Wires.
  9. loic

    loic New Member

    ok, is there any brand/model that are more recommended than others ?
  10. 99'HEARTBEAT

    99'HEARTBEAT Moderator Staff Member Platinum Contributor 1000 Posts 100 Posts

    You could go with Factory Plug Wires or Aftermarket Wires......MSD....Talyor.....or JBA.......you could Go either way.

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