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Buying a HV battery from doctorprius.com

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by lukaczer, Apr 4, 2020.

  1. lukaczer

    lukaczer Junior Member

    Joined:
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    Washigton, DC
    Vehicle:
    2020 Prius Prime
    Model:
    LE
    I am sorry- I wrote the wrong code in my previous post. I do have an old techstream and below is the codes that are current and haver been for a long time. It is p0420 that I am trying to understand. That is Catalyst efficiency below threshhold Bank 1. My reading indicates that It most often indicates a bad cat but can also be caused by a misreading by the O2 sensors and other issues. What I am trying to figure outis how to diagnose whether it could be an o2 sensor using techstream but I haven't been able to find much so far. Any ideas or guidance would be much appreciated!

    Thanks
    Steve File_000.jpeg
     
  2. Aegean

    Aegean Active Member

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    Vehicle:
    2006 Prius
    Model:
    ----USA----
    Here is my update too. It has been 11 months and 8000 miles since Doctorprius.com rebuilt my battery and still runs strong. MPG also remains high at 42 as it used be years ago. The last couple of years before the repair was creeping down close to 38.

    Of course after 15 years there is always something. I noticed last week that the water pump is leaking from the weep hole. I had replaced the water pump in 2011 at 55k with a cardone pump with lifetime warranty from Rockauto. I hope lifetime means lifetime and they will still honor the warranty 10 years later and 95k miles later.
     
  3. lukaczer

    lukaczer Junior Member

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    Vehicle:
    2020 Prius Prime
    Model:
    LE
    I love the Gen 2s- We have two of them an 06 and an 09. That being said I think they do have some weak points- the issues with the bladder type gas tanks- both cars have been affected by that; the combination meter black out issues which I fixed on the 06, and I worry about potential problems with the brake actuator which seems to run a lot on the 09. That is also a repair that I think is beyond my abilities to do. I would like to keep them both going for a while to come but I don't know how practical that will be. The economics of older cars is such that I just don't know if it makes sense to spend $1000's on fixing them when they are 12 and 15 years old.
     
  4. SFO

    SFO Senior Member

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    Were the repair manuals (linked above) not useful, or was the link broken?

    First I swapped the fuel injectors for a mix matched pair off ebay, cost $23 total. That worked for awhile, maybe 500 miles.

    Then installed a new Denso/OEM upstream A/F sensor, the p0420 went away for about 800 miles, until I filled it with 85 octane.

    You might try cleaning the MAF / throttle body, then disconnect the 12v for a couple of minutes, so the ECU can remap.

    Given your location, I would remove and sell ($$$$) that old cat in a heart beat, then toss in another new cat for $130+

    Then buy a new OEM A/F sensor, as they don't last forever.
     
    Raytheeagle likes this.
  5. mr_guy_mann

    mr_guy_mann Senior Member

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    Vehicle:
    2006 Prius
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    Four
    A P0420 can be caused by; 1)an exhaust leak (even a really small one) any where near or "upstream" of the downstream oxygen sensor. On an original exhaust system that is usually due to a worn gasket at the spring bolt flex connection at the exhaust manifold. 2)a faulty air fuel or oxygen sensor or 3) a bad catalytic converter.

    If it has a leak at the gasket it may only show up when driving the car as the engine shifts under accel/decel loading. The only replacement gasket that I have found to fit and seal properly is the OE part from Toyota.

    You can do a decent test of the air fuel (A/F) and oxygen (O2) sensors with techstream. Get the engine warmed up and then graph the two sensors. Perform a heavy (pedal to the floor) acceleration then coast/decel until the engine shuts off. At normal cruise with the ICE running steady, the A/F should fluctuate around 3.3V while the O2 is usually around 0.6 to 0.7V(if the cat is hot and functional- otherwise it will be something from 0 to 1V). On hard accel I expect the system to go "rich", with A/F going down to 2.3V or lower, and O2 reaching 0.9 to 1.0V. During fuel shutdown A/F goes up to 5.0V and O2 drops- 0.1 to 0.0V.

    The cat itself could be bad; the two things most likely to kill it are driving the car with an engine misfire, or having an engine that burns or consumes oil.

    Posted via the PriusChat mobile app.
     
  6. Aegean

    Aegean Active Member

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    ----USA----
    Just an update on my battery, 20k miles and 21 months later battery still working fine.
     
    Mendel Leisk likes this.