P0401 Check Engine Light

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Zoddy, May 4, 2018.

  1. Zoddy

    Zoddy New Member

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    Hi - I have prius 2010 98000 driven. I had P0401 with check engine light. Got Egr cleaned along with pipes, throttle body n MAP sensor. I didnt clean the intake manifold after opening, but client the passage it has to egr. Now the light is back almost about after 100k. What next should be done?
     
    #1 Zoddy, May 4, 2018
    Last edited by a moderator: May 4, 2018
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  2. Bay Stater

    Bay Stater Senior Member

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    You should clean the intake manifold too. There are four small return secondary ports that can clogged up with grime.

    Additional questions:
    Does your engine consume oil?
    Was the PCV valve replaced?
    You mentioned EGR cleaned. Does it include the EGR cooler?
     
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  3. RightOnTime

    RightOnTime Senior Member

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    Original 12v battery?
     
  4. NutzAboutBolts

    NutzAboutBolts Senior Member

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    You need to clean the whole egr system. It’s probably clogged with carbon. I would clean the egr cooler, pipe and intake manifold. If you cleaned it once before with the code and it went away, and now it has return, it’s probably has a build up of carbon over time.
     
  5. orenji

    orenji Senior Member

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    EGR valve been replaced? If not its covered by Toyota for 15 years or 150,000 miles.
     
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  6. Raytheeagle

    Raytheeagle Senior Member

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    While the valve is covered, that replacement won’t solve the underlying cause:(.

    Stories here point to the valve getting replaced, but everything else in the circuit being left “as-is”;).

    Cleaning the circuit is the best solution for the symptom (y).
     
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