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Function of O2 Sensor between Cat Converters

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by undertoad, Apr 26, 2020.

  1. undertoad

    undertoad Junior Member

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    Vehicle:
    2007 Prius
    Model:
    Five
    Some kind gentlemen stole the cat converters from my Prius while it was parked in the lot at work. The security cameras showed how little they feared getting caught. One took a piss right there on camera as the other got out tools. They jacked it up cut off the cats, and were backing out of the driveway in under 2 minutes.They should get a real job in the pits at Indy.

    So I had a shop replace the cats. The shop could not find any wires for the 02 sensor, and said they probsbly just jerked the whole assembly out, and the wire released at the next closest plug.

    Do any of you know where that plug might be?

    Also, because he could not find wires, he just plugged the hole where the O2 sensor would sit. Naturally, that triggers the check engine light. But what else does it trigger? Does it lean or enrich the mixture or anything else? I'd like to drive the car to work next week, if I can do so without harming the engine or anything else. I can work on fixing it next weekend.
     
  2. TMR-JWAP

    TMR-JWAP Senior Member

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    Touring
    The wires for that sensor pass through a rubber grommet in the passenger floorboard and connect to the cars wire harness on the passenger side of the center tunnel, under the carpet.
     
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  3. undertoad

    undertoad Junior Member

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    Thanks. Does this sensor affect the A/F ratio?
     
  4. MickyMatter

    MickyMatter Active Member

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    IDK, but usually it does, well it should.
    The Pre- and the post-catalyst signals are monitored to determine the catalyst efficiency. If the converter is not performing as expected, the ECU let the engine run leaner or richer to influence the catalyst temperature.
    Without the signal, the engine possibly could go into an emergency mode.
    Let me add that both, running too lean and running too rich, can damage the catalyst converter.

    SM-G950F ?
     
  5. MickyMatter

    MickyMatter Active Member

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    Right there Prius_II_Katalysator.JPG

    SM-G950F ?
     
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