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Gen3 Air Fuel Ratio Sensor Replacement

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by saak, Aug 2, 2016.

  1. saak

    saak Junior Member

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    I have a 2010 Prius with 160k km, need to install new Air Fuel Ratio (AF) sensor, got the original Denso sensor, can somebody please guide me how to access and replace AF sensor ? do I need to remove any thing from under the car to access it ? is it on driver side or passenger ? a full procedure or video would be very helpful. Thanks.
     
  2. CR94

    CR94 Senior Member

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    Do you mean the mass air flow sensor, or the oxygen sensor, which is the part most involved in reporting current air/fuel ratio?
     
  3. Raytheeagle

    Raytheeagle Senior Member

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    is this for the upstream or downstream sensor of the cat? Did you get a code that required you to replace the sensor? Or were there some symptoms leading to replacement?

    To answer your question the sensors are along the exhaust manifold. You'll have to remove the engine splash guard underneath to access the upstream sensor.
     
    #3 Raytheeagle, Aug 2, 2016
    Last edited: Aug 2, 2016
  4. NutzAboutBolts

    NutzAboutBolts Senior Member

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    The Air/fuel sensor should be by the exhaust manifold. Its right before the cat. You will have to remove the under body plastic panel to get access to it.
     
  5. Montgomery

    Montgomery Senior Member

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    Make sure you do this when the engine is cold...................just sayin....................
     
    Rebound likes this.
  6. NutzAboutBolts

    NutzAboutBolts Senior Member

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    lol for sure
     
  7. saak

    saak Junior Member

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    yes I have obd code P2196. I need to replace upstream oxygen sensor (air fuel ratio sensor). Is it on driver side or passenger, anyone has any document or video of replacement procedure.
     
  8. Raytheeagle

    Raytheeagle Senior Member

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    They are off the internal combustion engine, so on the passenger side.
     
  9. saak

    saak Junior Member

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    Mendel Leisk and Raytheeagle like this.
  10. Raytheeagle

    Raytheeagle Senior Member

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  11. Mendel Leisk

    Mendel Leisk Senior Member

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    In case anyone's scratching their head about the "No 2 Cylinder Head Cover", it's this:

    upload_2016-8-6_12-37-9.png

    BTW, when I click on links in your attachment, they WORK. For example wiper and cowl removal. Is the TechInfo paywall down. I kinda hate to ask this. Not complaining.