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Loud acceleration engine noise

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Deb White, Jul 8, 2017.

  1. Deb White

    Deb White New Member

    Joined:
    Jul 8, 2017
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    Location:
    WV
    Vehicle:
    2007 Prius
    Model:
    Two
    My '07 Prius, with 185,000 miles, is doing two things. Related or not, I don't know. When accelerating up a constant mountain incline, would knock itself out of cruise control and even though I would have my foot to the floor, in 70 mph zone, I was lucky to go 49 mph. I have traveled this road many, many times and this had never happened before. So, from then on, i wouldn't use cruise when I got to this area and in anticipation, I would speed up to 85 mph and just short of the top, it would slow to 55 mph. Now, when driving and I need to accelerate, even if I'm going 45 and need to increase to 55.0, it's now making a loud knocking, rattling noise. I saw/heard a YouTube video and the noise was said to be the catalytic converter. Should I have had an engine code come up for the catalytic converter, because I didn't. I wonder if after either knocking it out or replacing it, will I get the power and acceleration back?
     
    #1 Deb White, Jul 8, 2017
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,156
    50,059
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    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    welcome! what are you reading the codes with?
     
    #2 bisco, Jul 8, 2017
  3. DebWV

    DebWV Junior Member

    Joined:
    Jun 8, 2017
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    Location:
    West Virginia
    Vehicle:
    2007 Prius
    Model:
    Two
    Auto-Zone but there was no code for the catalytic converter. I had the converter busted out of it and walah, the loud knocking, rattling noise is gone! The next test will be when I have to pull a long, constant incline, to see if it knocks itself out of cruise and if I have the power back.
     
    #3 DebWV, Jul 9, 2017
    bisco likes this.
  4. Robert Meserole

    Robert Meserole Junior Member

    Joined:
    Sep 20, 2012
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    Vehicle:
    2007 Prius
    Model:
    IV
    Did it turn out to be the cat? If so did you replace it or just leave it after knocking out the internals? How has it affected your mpg?
     
    #4 Robert Meserole, Apr 12, 2018
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