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P0300 misfire detected need help

Discussion in 'General Chevy & GM Tech Questions' started by dallas65, Nov 20, 2009.

  1. dallas65

    dallas65 New Member

    I have a 2001 sierra ext-cab. It only does this when it is cold.
    During the summer and after it warms up it runs great.but when the engine is cold
    it runs rough and misfires and sometimes it dies.i think it is the iad sensor thats part of the maf sensor.. Am i right???

    99'HEARTBEAT Epic Member Staff Member 5+ Years ROTM Winner 1000 Posts Platinum Contributor

    The code P0300, is a Random or multiple misfire.If the last digit is a number other than zero it Corresponds to the cylinder number that is misfiring,Meaning P0302 would be the number 2 Cylinder.With a P0300 it doesn't tell you which Specifically which Cylinder or Cylinder's are misfiring.Some of the reason's for a misfire,
    could be Bad Plug or Wire,02 Senor,Faulty Coil pack,Faulty Fuel Injector.I would take a look at the wire's 1st and go from there.
  3. TritonBoulder47

    TritonBoulder47 Rockstar 4 Years 500 Posts

    Try cleaning your MAF and your throttle body... That's a simple, quick, and most of all cheap possible fix...
  4. unplugged

    unplugged Epic Member 5+ Years 1000 Posts

    Wife's girlfriend just had that problem. Wire on number two was bad. Replaced wires, and plugs since it was due for a tune up. Then had to go back and have the coil pack replaced.

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