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Check Engine Light (HCAC)

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by solace2483, Aug 6, 2008.

  1. solace2483

    solace2483 New Member

    Joined:
    Jul 8, 2008
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    Location:
    Chicago, IL
    Vehicle:
    2002 Prius
    I posted about a month ago about a repair Toyota said I needed. I have a 2002 with close to 120K miles. My check engine light came on and stayed on, they did the diagonstic and said I need to replace the HCAC valve cause it's not properly opening and closing. $1,700 for the part, total $2,000ish with labor.

    I didn't have that kind of money and I always feel like I am being taken advantage of since I am a young female that doesn't know much about cars.
    Anyway, last week the light turned off and has not come back on. It runs fine as usual and everything seems ok.

    Here is my question: Should I be concerned with it? I'm inclined to forget about it and go on with life since that light isn't in my face reminding me every time I drive her.
    What would you do in my situation? Fix it? Leave it?
     
  2. Sheepdog

    Sheepdog C'Mere Sheepie!

    Joined:
    Mar 12, 2008
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    Location:
    Sanford FLorida
    Vehicle:
    2008 Prius
    Model:
    II
    hmmm. I would consider taking it somewhere else to have them pull codes. If no error codes or some are found get them and give them to us so we can tell what it likely means. It's ok to not know everything. Im older now and think I know less and less all the time.
     
  3. solace2483

    solace2483 New Member

    Joined:
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    Location:
    Chicago, IL
    Vehicle:
    2002 Prius
    It cost me $102 at Toyota to get it checked out. I am not sure where I can find a mechanic that will be able to know about a hybrid that can look at it for me. I hate to spend another $100.
    I will see what I can find.
     
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Location:
    Green Valley, AZ
    Vehicle:
    2015 Prius
    Model:
    Two
    The HCAC valve (which is part of, and upstream from the catalytic converter) is a known weak point of Classic Prius. Cars driven on roads where salt is applied in the winter are especially likely to suffer failures.

    2G does not have this setup. Instead that model has the coolant heat recovery system, which produces its fair share of reliability issues.

    Since money is tight and the light went off, then you can forget about it for now. However, you will probably find that the light will come back on in the near future, especially in winter months. When that happens, you won't know whether the warning light is due to the HCAC valve, or some other problem.

    The implication of a failed HCAC valve is that your Prius will generate more emissions than necessary during the initial warmup period. Beyond that, the failure has no impact on vehicle driveability or safety.