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Sensors going off because of non oem catalytic converter?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Jcrew6311, Jan 27, 2023.

  1. Jcrew6311

    Jcrew6311 Junior Member

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    Catalytic converter was stolen about a year ago. Got a non oem replacement from my Toyota dealer put on because it was unknown when a OEM would be available. Fast forward, all year the check engine light has gone on and off every 20-30 miles and each time OBD2 reads it says needs OEM catalytic converter. 3 days ago red triangle came on, and today exclamation point with round circle around it came on along with vsc. I checked brake fluid and it's perfectly fine sitting between min and max. My neighbor seems to believe sensors are just going off because of the non oem converter. Checked obd2 today and still says needs OEM converter. Where do I go from here?
     
  2. ChapmanF

    ChapmanF Senior Member

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    Better to say what the codes are than just to give paraphrases. I assume the one being paraphrased as "needs OEM converter" is P0420, no?

    P0420 would not be causing your ((!)) and VSC lights to come on, and probably not the triangle. Those are likely telling you about something new from 3 days ago, not the year-old news about the converter.

    If the OBD tool you are using won't show you the codes behind the ((!)) and VSC lights, you can get those this way:

    Blink (a/k/a Flash) Codes – How to. | PriusChat

    Regrettably, though, that doesn't work for why the triangle light is on. (And there's a very good chance that you will have only code 58 on the ((!)) light and 51 on the VSC light, which only mean "go find out why your triangle light is on".)

    And only a scan tool capable of reading those codes will tell you.

    Besides Toyota Techstream, there are some third-party options reviewed here:

    Gen2 OBD2 app review | PriusChat
     
  3. PriusCamper

    PriusCamper Senior Member

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    If a Toyota Dealership did this job then I'd put pressure on them for installing a CAT that's not compatible and demand they resolve the problem at no cost to you. If they disagree you can go over their heads and call corporate customer service.
     
  4. Jcrew6311

    Jcrew6311 Junior Member

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    Yes p0420
     
  5. ChapmanF

    ChapmanF Senior Member

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    As I suspected.

    That still leaves finding out why the brake/VSC lights are on, and why the triangle is on.

    You can quickly find out why for the brake/VSC, from the blink codes. But they might only blink 58 and 51, which would leave only to find the reason for the triangle light.
     
  6. edthefox5

    edthefox5 Senior Member

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    Yup P420.

    A good non compliant cat should work perfectly on a G2. I had one installed for almost a year on mine and sold my cat on ebay $$.
    Sold my car a year a year later with this $129 cat and NO codes.

    Not sure why you used a Dealer to install it as its a very easy very straight forward cat install and a dealer will really bend you over at what $200+ an hour now labor?

    I brought my after market cat to a local muffler shop and they removed my OEM cat & installed my new after market cat for $80 and I duked the guy $20. Car actually ran better with this cheapo cat. BUT.. I did it to sell may Cat on eBay it was not stolen. 3 people I knew with a G2 had there cat ripped so I preemptively sold my cat.

    Now...having said that your O2 sensor or its wiring may be damaged and the dealer did not address that. The cat and its install may be fine but they just may have not noticed any damage to the O2 sensor wiring or using an after market O2 sensor. I assume your OEM cat got stolen and the awful shenanigans that go with it.
     
  7. Kasra

    Kasra Member

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    link to the aftermarket CAT?

    Posted via the PriusChat mobile app.
     
  8. rjparker

    rjparker Tu Humilde Sirviente

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    Here is one known to work.


    In our case the body shop that installed it initially misswired the replacement Bosch O2 sensor. Not your code but after the wiring was straightened out no codes at all.

    Some discussion about this cat including success stories at one shop.

    Napa 16337 Catalytic Converter? Check Engine Free? | PriusChat
     
  9. Jcrew6311

    Jcrew6311 Junior Member

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    Is the wiring something I can fix to offset the sensors going off, or would I have to bring it back into the shop to get that done?
     
  10. rjparker

    rjparker Tu Humilde Sirviente

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    No in your case the code is unlikely to be wiring. In our case it was wiring after a stolen cat was replaced with the 16337 which worked from an efficiency standpoint.