Sluggish Acceleration and MPG Reduction

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by EllenS2011, Apr 17, 2026.

  1. EllenS2011

    EllenS2011 New Member

    Joined:
    Apr 17, 2026
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    Location:
    Ohio
    Vehicle:
    2015 Prius
    Model:
    N/A
    I drive a 2015 Prius with about 125k miles on it. Oil is replaced every 5k miles, spark plugs/inverter coolant/transmission fluid/all air filters replaced 11 months ago. I've seen online that possible solutions may be EGR cleaning/replacement, battery fan cleaning, and/or battery replacement. Any other ideas or thoughts?
     
    #1 EllenS2011, Apr 17, 2026
  2. JC91006

    JC91006 Senior Member

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    Location:
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    Vehicle:
    2008 Prius
    Model:
    II
    Have you driven other Prius cars to compare?

    One thing that can help with a 2015 is you don't use the ECO setting on the drive selector. Use normal or power setting.
     
    #2 JC91006, Apr 17, 2026
  3. BiomedO1

    BiomedO1 Senior Member

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    Vehicle:
    2021 Prius Prime
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    LE
    FWIW: Your better off having a very good mechanic run diagnostics on the car; than spending money on guesses from the peanut gallery. If this is your first time behind the wheel of that vintage hybrid - they're all pretty gutless. IMHO; they start driving more like a regular car in the gen4 and gen5 versions; but your still going to be left behind at a stop light by a 60's VW bug.......
     
    #3 BiomedO1, Apr 17, 2026
    Last edited: Apr 17, 2026
  4. bisco

    bisco cookie crumbler

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    clean the throttle body. how many mpg's have you lost, and how are you measuring it?
    make sure all the wheels spin freely. how is the 12 volt health?
     
    #4 bisco, Apr 17, 2026
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