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Second Catalytic Converter Has Failed...Crap

Discussion in 'Generation 1 Prius Discussion' started by Benmuir, Dec 17, 2013.

  1. Benmuir

    Benmuir New Member

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    So I have a 2002 Toyota Prius that is currently in limp mode...

    Took it to the dealer for diagnostics and they said the Catalytic Converter has failed...So I went online, bought a new one and replaced it. The symptoms prior the Cat replacement were still there...mpg loss, power loss, and exhaust air was not exiting the end of the pipe but actually leaking out the connection point where the Cat and the manifold met.

    SO.

    Took it to muffler man, and they said the Second Catalytic Converter failed and was plugged. After doing HEAVY research on the internet, THERE IS NO AFTER MARKET PART! I am pissed. It is forcing me to buy the $1000 part! Looking at the Second Cat, there is a vacuum piece that attaches to what I believe opens the valve on the inside of the Cat.

    Question:
    Of course I know its probably not legal to do, so lets get passed that. Would my engine/car get damage if I removed the second catalytic converter and straight piped after the First Cat? I am on last resort... Anything helps!

    Thanks!
     

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    #1 Benmuir, Dec 17, 2013
  2. vaughnstark777

    vaughnstark777 Member

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    I have not looked at mine yet to see what your describing. Having said that, if their is no O2 sensor immediately before or after the cat it shouldn't be an issue

    SCH-I605 ?
     
    #2 vaughnstark777, Dec 17, 2013
  3. Benmuir

    Benmuir New Member

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    Yes it is after the O2 sensor but there is a vacuum tube connected. I cannot find anywhere what that tube does... and if it is vital to the car.
     
    #3 Benmuir, Dec 17, 2013
  4. vaughnstark777

    vaughnstark777 Member

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    It is probably used to heat up the o2 sensor. I would cut the cat at the beginning of the thickest portion behind the vacuum motor. Then remove all the ceramic material and weld it bac together. Make a small cut at a 90 degree angle to the maincut before you finish the main cut so when you weld it back together it is aligned correctly.

    SCH-I605 ?
     
    #4 vaughnstark777, Dec 17, 2013
  5. vaughnstark777

    vaughnstark777 Member

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    Looking at that vacuum motor I am almost certian it is used to heat up the o2 sensor quicker therefore putting the vehicle into "closed loop" quicker. So even if that vacuum motor doesn't work it still should go into "closed loop" it may just take longer.

    SCH-I605 ?
     
    #5 vaughnstark777, Dec 17, 2013
  6. frodoz737

    frodoz737 Top Wrench

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    Some states do not require you to use the Factory OEM Cat. Where are you located.
     
    #6 frodoz737, Dec 17, 2013
  7. ChapmanF

    ChapmanF Senior Member

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    Catalytic converters that repeatedly die generally mean there is an engine condition that's killing them. Persistent misfiring or oil consumption will do it, by sending unburned HC straight back to the cat to burn it up from the inside. So the first thing I'd do at this point is look for what's up with the engine that's killing your cats. Fix that, and you'll probably get better performance/mileage too, cat or no cat. Have you pulled engine codes?

    Hmm, what do you mean by "anywhere" exactly? There's lots of information about it all over this forum and elsewhere on the web, not to mention at techinfo.toyota.com. A lot of sites give pretty good overall introductions to the technology in Prius - if you think you might keep the car a while, it's probably in your interest to look some of them up.

    This one has an ok description of the HCAC valve on pages 2-9 to 2-12.

    [edit: just beware, it describes more than one Prius model ... we don't have the coolant heat storage tank in Gen 1, for example.]

    Good luck!
    -Chap
     
    #7 ChapmanF, Dec 18, 2013
    usnavystgc, ftl and bwilson4web like this.
  8. usnavystgc

    usnavystgc Die Hard DIYer and Ebike enthusiast.

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    You might be able to get away with unseizing the bypass valve. It is likely stuck closed. I have seen numerous threads on here about people doing just that. There are numerous ways of doing it but the common theme is to use a penetrating liquid like wd 40 and work the valve back and forth. Then you need to grease it with a heat resistant grease to keep it operating.
     
    #8 usnavystgc, Dec 19, 2013
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