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2010 Prius Gen 3, Cylinder 2 Misfire

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by MSHARA, Oct 20, 2022.

  1. MSHARA

    MSHARA New Member

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    2010 Prius
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    III
    I own a 2010 Prius with over 230000 Miles. Engine was replaced with a used engine, about 3 years ago @ around 170K Miles. Started getting check engine light due to cylinder 2 misfire. Car drives fine except a little rough idle and minor vibration. After Spark Plugs and Ignition Coils replacement, cleaning of the EGR system (including manifold), problem still exists. Switched injectors to see if problem will show up at a different cylinder, but it stays at cylinder 2. No loss of water and tests have been done to rule out the head gasket failure. Hope someone can steer me in the right direction. Thx
     
  2. Mendel Leisk

    Mendel Leisk Senior Member

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    Those two statements seem at odds with each other. The plugs were swapped with the coils?

    The second statement seems a little tentative too: who did the tests, what tests? Was a leak-down test done?

    Can you provide history on when the EGR was cleaned, dates/miles? Was the intake manifold done at same time? Who did the cleaning, and are you sure it was thorough?

    If, for example, EGR cleaning was done for first time, on the heels of the latest head gasket failure symptoms manifesting: too little, too late?
     
  3. MSHARA

    MSHARA New Member

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    III
    Hello Mandel,

    Thanks for responding. I will try to do a better job of explaining the issue and answer your questions. Check engine light came on a few months ago at about 220K miles. There was no noticeable vibration until recently and I took the car to a local mechanic last week. He hooked up his code reader and noticed the cylinder 2 misfire. He did the following:

    1. Replaced Spark Plugs and Ignition Coils. Cylinder 2 misfire problem did not go away.
    2. Cleaned EGR Valve, Pipe and Manifold. Cylinder 2 misfire problem did not go away.
    3. Performed a leak down test and tested coolant for hydrocarbons. Did not find any issues.
    4. Switched the Fuel Injector for #2 Cylinder with one of the others. Misfire still showed up at Cylinder #2.

    At this point he suggested that I have the dealer diagnose the problem and charged me only for the parts (no labor). Dealer charged me $175 just to tell me that they did not find any issues with the spark plugs, coils or EGR. Furthermore they said it will be an additional $550 charge for next step which will be to check the fuel injectors. I did not feel like waisting any more money with the dealer.
     
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    Touring
    Just 230k without EGR cleaning, and a misfire code that stays with cylinder 2, points to head gasket. Second opinion leak down test?
     
  5. MSHARA

    MSHARA New Member

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    OK. I will take it in for a second opinion. Thx
     
    Mendel Leisk likes this.