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2005 Prius P0505 Error code

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by 1Countrylivin, Mar 24, 2015.

  1. 1Countrylivin

    1Countrylivin Junior Member

    Joined:
    Mar 24, 2015
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    Location:
    Ohio
    Vehicle:
    2005 Prius
    Model:
    II
    Hello,

    I have a 2005 Prius with almost 244,000 mile and about a week and a half ago the check engine light came on. I went to an Advanced Auto and had them read the code for me, which came back with a P0505 error code. I have read several things on web that this code is a Idle Air Controller related.

    I also have read that this could be to a loose or bad PCV valve, an air leak in the vacuum lines, throttle motor shaft might be binding, or a failed engine ECM.

    The car runs and idle just fine, no stalling or a rough idling. The only problem that is obvious is that when the car is warm and I come to a stop or put in park, the motor will not shut off.

    Which one of these would cause this to happen? Or could this be due to a MAF sensor that needs cleaned or replaced?

    Any help would be appreciated.

    Thanks
     
    #1 1Countrylivin, Mar 24, 2015
    Last edited: Mar 24, 2015
  2. valde3

    valde3 Senior Member

    Joined:
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    Location:
    Finland
    Vehicle:
    2004 Prius
    Start by cleaning the throttle plate. Disconnect the 12V so that it learns the new idle position. I think all of those could cause it not to shut down but throttle plate is probably most likely.

    In a Prius engine problems behave totally different than in normal car. If you want to test how engine is actually running:
    -start it (e-brake on)
    -wait for engine to shut down
    -push just enough throttle pedal to start the engine
    -put it in neutral
    -now engine is working as in normal car
    -don’t let the hv-battery run empty
    -go back to normal just by shifting out of neutral (for example just press the park button)
     
    #2 valde3, Mar 24, 2015
    Last edited: Mar 24, 2015
  3. 1Countrylivin

    1Countrylivin Junior Member

    Joined:
    Mar 24, 2015
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    Location:
    Ohio
    Vehicle:
    2005 Prius
    Model:
    II
    I wanted to thank you valde3, I finally had cooperation from the weather this past weekend and disconnected the battery and cleaned the throttle plate. While I was at it I cleaned the MAS sensor with the proper spray I picked up at Advanced Auto along with the throttle plate cleaner. Man was it pretty dirty, I almost used a half a can cleaning the throttle plate. After hooking up the battery and starting, no check engine light, and after a minute from a cold start the engine quit idling like it suppose to.

    Thanks again.
     
  4. bisco

    bisco cookie crumbler

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    Location:
    boston
    Vehicle:
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    Plug-in Base
    well done valde!(y)