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P0420 question, New member

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by hec983, Aug 19, 2023.

  1. hec983

    hec983 New Member

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    new to the forum. I just got a 2008 Prius with 200k for a really good price. The car drives great. However it throws the p0420 previos owner told me her mechanic said the front exhaust pipe is the catalytic converter need to be replaced. The code goes off and they after a while comes back and then off again. Still has the original cat. What’s the best route to fixed this issue. I’m planning on keep in the car for a while. Pretty comfy ride honestly I love it. Thanks in advance guys


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    #1 hec983, Aug 19, 2023
  2. bisco

    bisco cookie crumbler

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    #2 bisco, Aug 19, 2023
  3. PriusCamper

    PriusCamper Senior Member

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    Aftermarket replacement cats are less than a $100 these days and its an easy DIY install with no welding required. However you could also try replacing your 02 sensor as sometimes they go bad.

    As long as your check engine light is not on all the time you can procrastinate on it. But once its on for good, you'll want to fix it because once that warning light is always on, you'll no longer get a warning about additional problems, which could massively increase repair costs.
     
    #3 PriusCamper, Aug 19, 2023
  4. PriusDummy

    PriusDummy New Member

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    What are the best aftermarket cats that prevent P0420?
    I've lived with it the past 6 months, guy I bought it from said aftermarket cats always show the P0420
     
    #4 PriusDummy, Aug 19, 2023
  5. hec983

    hec983 New Member

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    Thank you for all the reply. Which cats do you recommend


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    #5 hec983, Aug 19, 2023
  6. bisco

    bisco cookie crumbler

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    one of my links named the cat, iirc
     
    #6 bisco, Aug 19, 2023
  7. PriusCamper

    PriusCamper Senior Member

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    Here's the one we traditionally recommend on here... It's direct fit is more reliable than others and its only one I know of at this price point that comes with paperwork for a 5 year 50K mile warranty. https://www.ebay.com/itm/193690871378
     
    #7 PriusCamper, Aug 19, 2023
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  8. JC91006

    JC91006 Senior Member

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    If you end up buying an aftermarket cat, make sure you don't give away the original failed cat. That is worth a lot of money $$$ (even failed)
     
    #8 JC91006, Aug 20, 2023
  9. hec983

    hec983 New Member

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    Good to know thank you very much.


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    #9 hec983, Aug 20, 2023
  10. hurricos

    hurricos New Member

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    Hey there, new member in the same boat ('08 Prius with 204K). I'll try that replacement; if I'm not mistaken it will require me to make a cut if my exhaust pipe is OEM, yes? Angle-grinder or Dremel?

    Finally ... where the f do I sell my fouled OEM cat? I know there's a black market for these and I want to avoid it; I assume that I'll need to document my removal.

    FWIW, I think I know what destroyed my OEM cat, the sparks were the factory originals and I've burned 1qt after 2000 miles, but I'm not too worried -- I just need a reliable backup for my '01 Insight (I bought the Prius to haul an engine for it) and don't plan to drive it too much.
     
    #10 hurricos, Aug 20, 2023
  11. PriusCamper

    PriusCamper Senior Member

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    Sawzall is easiest fastest standard... Angle grinder or dremel will probably set your hair on fire...

    As for selling your old one, not a lot of options or good prices after the Cat theft crime spree. But try these folks: https://rrcats.com/
     
    #11 PriusCamper, Aug 21, 2023
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