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P0420 Code Catalytic Converter Failure 2005 Prius CA

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by barrystein, Aug 23, 2018.

  1. barrystein

    barrystein Junior Member

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    2005 Prius
    My car is throwing a P0420 Code. Dealer says I need a Catalytic Converter.
    We are at 189,000 miles - so we are out of the 150,000 warranty in CA.

    I have called Toyota Corporate to see if they will help. They will get back to me next week. I am being quoted $2800 by the dealer

    CA has strict rules, and we can only use OEM part, though the dealer said they'd put a junk yard part in it, as it would be OEM, however I can't find a junk yard that will sell one.

    Aftermarket doesn't seem to be available as well.

    Someone said that replacing the oxygen sensors might fix the problem as well -- any thoughts on that.

    We don't have to smog the car till March 2019. The codes have been cleared, check engine light is off, but we are expecting the P0420 code to trigger the check engine light again. Car runs fine....
    any advice?
     
  2. audiodave

    audiodave Active Member

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    I had a magnaflo aftermarket cat sent to a friend in another state then sent to me in Cali. Installed myself. Two smog checks and nobody looked under the car. Not legal but it functions like it should be. Bs California.
    Otherwise deal with it until you have to. But changing the rear o2 may also fix it but I never tried it.

    Posted via the PriusChat mobile app.
     
  3. bernie3015

    bernie3015 Member

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    O2 Sensor Spacer Adapter Extender should get rid of the error code and the last smog inspector I used only looked at the forward end of the catalytic converter to see if it was California certified.
    Another solution is to take the car to a neighboring state where you can replace the converter at a reasonable price and sell it there.

    The california emmission control warranty in 2007 was and probably still is 15 year or 150,000 miles and includes salvage tiles. The car manufactures have to pay for this somehow. California approves very few aftermarket Catalytic converter. My suspicion is that this is so the manufactures can get reimbursed by selling their OEM products after the warranty expires.
     
  4. bernie3015

    bernie3015 Member

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    Here is another solution. From my experience with an 2001 and 2007 Prius (same engine) the engine start to burn oil between 150k and 200k. When that happens the catalytic converters get gummed up and start to fail. So you can try the products that clean the catalytic converter and then use oil additives that prevent oil consumption.
     
  5. barrystein

    barrystein Junior Member

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    Thanks for that. Where do I find:
    O2 Sensor Spacer Adapter Extender
    Products that claim to clean the catalytic converter
    what oil additives the prevent oil consumption are safe to use on a 2005 prius?
     
  6. audiodave

    audiodave Active Member

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    No gumming of my original cat. Looks clean. But 225,000 miles on it when I got the code.

    Posted via the PriusChat mobile app.
     
  7. audiodave

    audiodave Active Member

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    Offer great warranty to the newer buyer but screw the guy who keeps the car past the warranty.

    Posted via the PriusChat mobile app.
     
  8. MichaelKnight

    MichaelKnight Junior Member

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    I think this is what Bernie posted above......I cannot add anything nor have I tried this....
     
  9. exstudent

    exstudent Senior Member

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    Correct, New cars get 15yr/150,000miles warranty. Commercial vehicles have a different warranty duration.

    INCORRECT, vehicles with a salvage title are NOT eligible for ANY manufacture warranty and recalls!
    Why would you think otherwise?

    Imagine a vehicle was involved in a flood, fire, sever accident. Insurance will write the car off and sell it at autction to a dismantler or an unscropulous rebuilder. If you were an automaker, would you accept warranty and recall liability for such a vehicle?

    SALVAGE = NO warranty, NO recalls, majority of the time a horrible purchase mistake.

    INCORRECT. California’s Air Resource Board required Catalytic Converter manufactures to submit testing data proving that their replacement converters provided the same level or lower levels of polution compared to the OEM part. Also, the replacement part is required to be warranted for a far longer period than one year/unlimited miles. The aftermarket manufactures don’t want to pay for the testing and provide the longer warranty. Thus only the OEM Catalytic Converters are the only approved replacement parts.

    Speculation that is incorrect is incorrect.

    I remember reading someone who used a magnaflow outside of California. Unfortunately for that person, the Cat only lasted one year, just after warranty. This happend twice for the unlucky guy. In his case, you get what you pay for.
     
    #9 exstudent, Aug 25, 2018
    Last edited: Aug 25, 2018
  10. audiodave

    audiodave Active Member

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    I've ran a magnaflo on mine for two years on the Prius and probably 8 years on my S10, no problems. Magnaflo a better quality as far as I'm concerned.

    Posted via the PriusChat mobile app.
     
  11. exstudent

    exstudent Senior Member

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    A four leaf clover.

    No oil additives prevent oil consumption. Not driving is the only thing to prevent oil consumption; engine not moving=not wearing out. The engine is consuming oil b/c the piston rings and/or valve seal guidaes are worn out, which contributes to the death of the Cat. I also assume the Cat was not physically damaged (ie road debris), or the precious metals in the Cat not being worn out; both possibilities easy to check.

    Yes some people swear by “snake oil additive A,”or other products like Sea Foam. And yes these same snakes have “testing” that shows it works for them, (but not for you). Remember, some one will win the lotto, just not you, or me. These products sell well because of the allure and appeal of spending a few dollars to avoid spending hunderds if not a few thousand.

    Replacement of the Cat is usu required, but it too will die early if the engine is consuming a lot of oil. Fixing the oil consumption (engine replacement new/used, engine rebuilding, or ring/guide replacement) is the best long term solution (pricey fix if you have to pay for labor). Yes, many attempt to replace the O2 sensor of hoping this will avoid the inevitible.
     
    audiodave likes this.
  12. barrystein

    barrystein Junior Member

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    Dealer claims that after they cleared the P0420 code, the test showed that the Catalytic Converter failing, below threshold efficiency. So I am not sure if the car is still throwing the P0420 code. The check engine light is not on. I Bought Foseal OBDII Dongle and used OBD Car Doctor and Car Scanner. Neither show the P0420 Code. Does the dealer have something that shows more codes? Would the BlueDriver Bluetooth Professional OBDII Scan Tool show me more codes.
     
  13. audiodave

    audiodave Active Member

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    How many miles have you driven it? Takes 30-50 miles or so to see if code will come back.

    Posted via the PriusChat mobile app.
     
  14. barrystein

    barrystein Junior Member

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    It has been driven 500 miles since the codes were cleared. OBD Car Doctor and Car Scanner both show that many miles driven since codes cleared. So it sounds like the dealer did not get the P0420 code again - they must have tested the Cat some other way. I plan to call tomorrow to clarify
     
  15. audiodave

    audiodave Active Member

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    Unless they tested the tail pipe emissions. Even at that with two cats tough to tell.

    Posted via the PriusChat mobile app.
     
  16. Priusshane

    Priusshane New Member

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    Hi there
    Have a good used ca cat off a 07 to take care of the p0420
     
    douglasjre likes this.
  17. Classic Car Guy

    Classic Car Guy Active Member

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    Thread resurrection. Maybe this is worth a shot for I need help on my car.
    I want to follow up with my 2007.
    The "Check Engine just lit up 2 nights ago as I was pulling in the driveway.
    I put the scan tool today and its says "1 fault" and it displays this:
    P0420 01
    P0420 02
    I was also a victim of a stolen catalytic converter and replaced mine with aftermarket 2 years ago. I bought the replacement aftermarket probably 120 dollars and have it installed professionally. Basically no leaks.
    At first time replaced, it was running nicely with above 45 mpg on the screen. After a year it went down to 41-43 mpg.
    My car is fully tuned up and serviced as what the book requires on maintenance service.
    Presently it has 151k miles and eats a 1/2 a pint every 4500-5000 miles of driving. I use 87 regular gasoline.
    What I did yesterday is I, I cleaned the throttle body and intake, run it half an hour, change oil and filter 10w/30 Quaker State synthetic (as I always use every 5,000 miles, air filter is clean and not due yet so I installed it back. I reset the check engine light using the scan tool and maintenance after the change oil. After 100 miles of city and highway driving, the Check Engine turn on again. I also want to add that besides the check engine light, the car still runs beautiful. Here is my last screen right when I was heading home. Any suggestions? Thanks.
    If I need to change the 02 sensor and it could be a part of it, I wont mind changing them. with the original Toyota parts. The only thing that I cant afford to put back is the original catalytic. its too expensive.

    [​IMG]
     
  18. douglasjre

    douglasjre Senior Member

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    "Someone said" LMAO

    Love the infamous "someone's" who said something. Do u get legal advice from waitresses?

    Toyota has their own used parts. They rebuild Avalon rack units and such. Parts dept has inventory and special codes for rebuilt units. Ask them re: cats
     
  19. douglasjre

    douglasjre Senior Member

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    Car doctor is junk. Dealer computer. Period
     
  20. mr_guy_mann

    mr_guy_mann Senior Member

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    Umm... Why post the exact same thing in 4 or 5 places? The answer is going to to be the same.

    You've gotten pretty good service from your $120 cat, and it's likely time for another one.

    Bad sensors can cause a false cat code. As can (small) exhaust leaks. Can you test the sensors to see if they work properly, or so you want to fire the parts cannon?

    Posted via the PriusChat mobile app.
     
    #20 mr_guy_mann, Sep 27, 2023
    Last edited: Sep 27, 2023
    Brian1954 likes this.