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Catalytic converter: OEM vs. Universal

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by AllenZ, Apr 29, 2016.

  1. AllenZ

    AllenZ Active Member

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    My 2004's catalytic converter is out now, can't pass emission test.

    On eBay, there are two kinds of converters: OEM vs. Universal:

    OEM: $234.95
    Toyota Prius 2004 2005 2006 2007 2008 2009 Direct Fit Catalytic Converter | eBay

    Universal: $45.60
    Eastern Universal Catalytic Converter Standard Catalyst 2” Pipe 10” Body 70257 | eBay

    It seems like the OEM has two converters connected in series, if I buy the universal version, do I need to also buy TWO of them, and add some connecting pipes?

    Another thought: How about oxygen sensor? On the universal, there are 3 versions: No sensor hole; One sensor hole; Two sensor holes. The link above is "no sensor hole" version, which the seller claim fits 2004 Prius.

    So I am confused, and need someone to give me some idea.

    Also, if I need to buy TWO converters plus pipes, guess the total cost will be around $120 something. Compare to the OEM of $234.95, not much difference. Maybe the installation labor will be less for OEM version too?

    My 2004 Prius has 234K on it, with fair body conditions, probably worth less than $3500, just to keep that in mind when talking about maintenance cost. The Hybrid battery is a little weak but still works. The engine burns oil at 1 bottle/1K miles.

    Other than that, runs very well.

    Thanks as always!
     
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  2. AllenZ

    AllenZ Active Member

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    Oh, if anyone can tell me how much labor for private mechanics to install the OEM converter (no welding), or Universal Converter (with welding job), I really appreciate!
     
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  3. JC91006

    JC91006 Senior Member

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    I bought the magnaflow catalytic converter and it's a perfect fit for the Prius, sold on Amazon for $100. Cost me $40 to weld it on but most people I've read about got it installed for around $80-$150

    Magnaflow 99205HM Universal Catalytic Converter (Non CARB compliant)
     
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  4. Mendel Leisk

    Mendel Leisk Senior Member

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    $235 Doesn't seem bad, especially if it's a perfect fit from the get go.
     
  5. AllenZ

    AllenZ Active Member

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    Thanks for the info!

    I wonder did you replace just one converter? Or you bought two? From OEM version, it looks like there are two converters for Prius on the same pipe.

    Also, does it has holes for oxygen sensor?

    Thanks!

    Allen
     
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  6. JC91006

    JC91006 Senior Member

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    The one that goes bad is usually the one that's closest to the manifold. You just cut off the old one and weld on the new one. No need to do anything with the oxygen sensor
     
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  7. kswahl1

    kswahl1 Junior Member

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    I'm going through this fiasco right now as well. Just got back from the muffler shop. You need to find out what type of emissions your car is compliant with. CARB i.e. California or non-CARB. From my understanding if your car is CARB compliant the cheap replacement cats won't work and your check engine light will stay on. You'll need to get a CARB compliant catalytic converter.
     
  8. kswahl1

    kswahl1 Junior Member

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    Vehicles licensed outside of California, but built to California emissions standards, may have a physical difference from a vehicle built to Federal emissions standards. (If your vehicle is manufactured to California emissions standards, it cannot use a converter that is cataloged as Federal only). You need to reference your vehicles emissions sticker before purchasing a Walker converter. A vehicle licensed in the State of California must use a CARB approved converter.

    WALKER® EXHAUST SYSTEMS :: Catalytic Converter FAQ
     
  9. JC91006

    JC91006 Senior Member

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    A non carb compliant catalytic converter will still work, the check engine light will turn off. It's just not legal to use that part in CA
     
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  10. kswahl1

    kswahl1 Junior Member

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    Good to know. Thanks!
     
  11. AllenZ

    AllenZ Active Member

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    Good that I am not in CARB state!
     
  12. Mendel Leisk

    Mendel Leisk Senior Member

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    For what, an extra $100 or so, you can keep it stock, avoid possible gotchas, AND keep the air cleaner?

    Meh.
     
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  13. fitnspark

    fitnspark Junior Member

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    Can you tell me if what converter you used for your replacement and if you passed your emission's test? I only have 10 days to get mine fixed or I'll not be able to renew my plates in Illinois. I've been out of town for the past 3 weeks and almost all year with medical issues so I was shocked to see the reminder that I needed the emissions test done by the end of the month. I have a Prius that says California on the sticker and I can't afford to get this wrong. I need the car because of the medical issues going on and I really don't have the money to mess it up. Illinois does not have CARB testing but the car sticker says CAL so if I put a non factory replacement on the car will the codes and light reset and pass or will I still be in trouble? I have a 2008 Prius with about 135000 miles. Unfortunately the family medical issues have been first on the list so the service engine light has been on for several months. Can you give me any solid advice? I don't even know if I am writing this question properly in this forum. Thank you for any help.
     
  14. AllenZ

    AllenZ Active Member

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    Get this is the safest for you, but cost more, $235:
    Toyota Prius 2004 2005 2006 2007 2008 2009 Direct Fit Catalytic Converter | eBay

    Or get this is OK, I installed it, the code is gone, but have not go re-test the emission yet, should not have problem. $46
    Eastern Universal Catalytic Converter Standard Catalyst 2” Pipe 10” Body 70257 | eBay

    In both cases, the installation is about $200, because it needs at least welding job on one side.

    Or you can go to a muffler shop to get a quote.

    I think since you are in IL, even if your car is CARB, you don't need to comply to their standard.

    Good luck!

    Allen
     
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  15. James Analytic

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    What needs welding?

    Maybe I'm missing something and need to watch some more videos. From my grossly inadequate review regarding this matter, appears two bolts with springs and a gasket on the manifold and press fit and clamp on the tailpipe end. I'm looking at the eBay and Amazon direct fit ~$60 to ~$110 ones.

    I'm getting ~30 to ~38mpg as well. How much mpg improvement should I expect to see once the above cat and Denso sensors are replaced and assuming those P0031, P0037 and P2238 codes reset and don't re-appear?
     
    #15 James Analytic, Mar 1, 2023
    Last edited: Mar 1, 2023
  16. alftoy

    alftoy Senior Member

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    The cat they are talking about is not direct fit, not the same as the one you are looking at on Amazon.

    Google Magnaflow 99205HM Universal Catalytic Converter (Non CARB compliant)
     
  17. James Analytic

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    Makes sense, though I read literally as: "In both cases, the installation is about $200, because it needs at least welding job on one side."
     
  18. James Analytic

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    I wound up investing in the "Catalytic Converter for 2004 2005 2006 2007 2008 2009 Toyota Prius 1.5L" AutoShack one for $67.54 delivered for and taxed for $71.59. https://www.ebay.com/itm/352894459085

    For the downstream O2 sensor, I installed a new "Denso 234-4623 Downstream Oxygen Sensor with 23” 4-Wire Square Plug Harness for Calif. Equip"


    Now I only have the P0031 and P2238 AF related codes, though the monitoring appears to be incomplete for a few tests where the P2238 is listed as Pending only.

    I was actually surprised from what I read regarding the donuts, where my I guess OEM manifold to "custom exhaust" pipe was trashed. Though the rear donut was in good condition from the donor yard car. So I used what came with the cat for the manifold donut and went to Autozone to get a 1-3/4" stainless steel exhaust pipe clamp since the one that came with seemed a bit large. Amazingly, and to my total surprise, I felt no exhaust leaks from any of the seams I could get my hand around.

    Now, I hear my engine making noises and significantly less exhaust sound. Seems to feel a little smoother on the acceleration as well and not vibrating like I've noticed before when starting.

    Since my drivers side HID is doing the "flickering and not working erratically" thing, I decided not to drive anymore until the next day. On another note, I scored a pair of Halogen headlight assemblies on the last 50% of sale at the yard along with some bulbs with connectors that look good enough and will swap those in when I get the time.

    First things first, getting rid of the trouble lights and codes.
     
    #18 James Analytic, Mar 21, 2023
    Last edited: Mar 21, 2023