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open or short in engine wire harness p0302

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by freebird1, Nov 11, 2021.

  1. freebird1

    freebird1 Junior Member

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    Location:
    Dallas, TX
    Vehicle:
    2010 Prius
    Model:
    Three
    2010 prius gen 3 ,check engine light on,car does get into ready mode drives
    Im getting this code today open or short in engine wire harness p0302
    replaced all 4 spark plugs and coil also replaced on P0301 code before
    also car shakes turning right in motion ,could be another issue
     

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  2. JC91006

    JC91006 Senior Member

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    Vehicle:
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    II
    How many miles on the car? That code means there's a misfire in cylinder 2. There could be mutiple causes for that error
     
  3. freebird1

    freebird1 Junior Member

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    Location:
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    Three
    175+
    yes codes not reliable as older car ,or other issues
    getting random before 301 fixed with change coil and all 4 sparks but still got again 301/302/303/304
    after long drive today got check engine light and 302
     
  4. JC91006

    JC91006 Senior Member

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    II
    unfortunately that sounds like you have bad fuel injectors or a bad head gasket. These cars are well known for headgasket failure at around the 200k miles mark.
     
    freebird1 likes this.
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    There's unsubstantiated rumours here, that 3rd gens with those miles are prone to head gasket failure, typically at cylinder one or two, if the EGR (Exhaust Gas Recirculation) circuit, incluiding the Intake Manifold, has not been cleaned of carbon build-up.

    I'd try a leak-down test to see what the head gasket condition is.

    Also, is engine coolant reservoir level stable?

    I'd get on the EGR cleaning ASAP; more info in my signature.