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4th Gen DIY heat exchanger bypass solution

Discussion in 'Gen 4 Prius Main Forum' started by texasdiver, Jul 28, 2022.

  1. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Toyota after-sale care, standing behind their product, is notably lacking. I get that there’s a simple workaround, but is this their new “mission statement”:

    ignore, dodge and remain silent when there’s an issue, and eventually all the cars involved will fail or rust out.
     
  2. Poa

    Poa Junior Member

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    Any Californian knew would this "fix" pass ca smog test?
     
  3. BiomedO1

    BiomedO1 Senior Member

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    It depends on how nicely you've got it tucked away. The more OEM the look, the better chances it gets overlooked. They're usually looking at the CAT and ensuring it's either CARB certified or OEM.
    If hoses are dangling down there with zip-ties, they'll take notice and look harder.

    Hope this helps....
     
  4. Dusttttt

    Dusttttt Junior Member

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    2017 Prius here. I just checked and saw P0128 code, which says its the thermostat. Two days ago my car had a lot of white exhaust, but it didn't do that yesterday. My coolant reservoir is dry after just driving 5 miles and I have filled it up now three times in a row. Does this sound like the heat exchanger? Or the thermostat?
     
  5. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Probably the heat exchanger. Any signs of pink crust, around water pump or thermostat?
     
  6. black_jmyntrn

    black_jmyntrn Senior Member

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    id take it to the dealership as they should cover it all and be sure to have them do a compression test.. or.. don't remind them and when they fix the TSB... and next thing you know you need a head gasket.. argue that they didn't perform a compression test and you believe the TSB to be the cause of the now need for a new motor...
     
  7. Dusttttt

    Dusttttt Junior Member

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    I did not see any pink crust around those areas. If this is the heat exchanger, how does one remove all the coolant that’s still inside of it? Do they burn it off or do they have to replace the catalytic converter.
     
  8. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    AFAIK the only option with a leaking Exhaust Heat Recover component is replacement. It’s coupled with the Catalytic Converter, a single “part”, and accordingly quite expensive.
     
  9. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Geez, this seems to good to be true:

    17410-37A00 - Toyota Parts Deal

    Maybe too, you're buying brand new, but it's got the defective welds? There's numerous supersessions, prices $1000~2000 USD.

    (I first looked it up on Amayama; they're out of stock, of all the the parts numbers, but at least then you can copy/paste those numbers and search with google.)
     
    #109 Mendel Leisk, Oct 15, 2024
    Last edited: Oct 15, 2024
    Dusttttt likes this.
  10. Dusttttt

    Dusttttt Junior Member

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    I would love to take this to the dealership
    I don't have this trouble code-- (MIL ON DTC P148F00), but I do have P0128 code. I just called Toyota customer service and gave them my vin and asked if the TSB would cover my car and they said that it is vin specific and that my vin isn't included in this TSB. Do you know if that's true? Because the next thing they told me to do was just go to the dealer and have them diagnose it officially.
     
  11. BiomedO1

    BiomedO1 Senior Member

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    It's part of the emissions system; check CARB regulations to see if your within Ca state mandates. If you meet all CARB regulations, years and mileages, They are required by state law to fix it for free..... Federal statues are much looser...

    Hope this helps....
     
    black_jmyntrn likes this.
  12. vvillovv

    vvillovv Senior Member

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    Does the Gen 4 Prius even have a heat exchanger? It'd be overkill (imo) if it does.
     
  13. vvillovv

    vvillovv Senior Member

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    @Dusttttt you might want to give GM gasketmasters a call and ask them if they know, since I believe they are the ones that figured out the heat exchanger bypass for the Gen4 Prime.
     
  14. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    Does it ever, infamous for leaking too.