1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Faint clunking noise coming from 07 Prius when not moving

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by shumiron, Feb 7, 2023.

  1. shumiron

    shumiron Junior Member

    Joined:
    Apr 20, 2007
    8
    1
    0
    When I am in the car parked with the car off I can hear a repeating faint clunking sound that lasts for a few seconds then repeats at intervals of a couple minutes or so. This goes on constantly and does not matter if the key is with me or not. I just replaced the inverter coolant pump and all seems good with the car.

    Car info - Base model without keyless entry
    - 211,000 miles
    - Runs excellent but low MPG. less than 40 MPG
     
    Tombukt2 likes this.
  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    7,790
    1,348
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    I had a front caliper not releasing causing loss of about 4 mpg.
     
  3. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    7,790
    1,348
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Check you're rear brakes no leaks etc.
     
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    is it under the hood?
     
  5. SFO

    SFO Senior Member

    Joined:
    Feb 7, 2017
    5,286
    4,225
    0
    Location:
    Northern California
    Vehicle:
    2007 Prius
    Model:
    N/A
    Could this be the brake accumulator going out?

    What does the 12v battery measure at the jump points under the hood?
     
  6. mr_guy_mann

    mr_guy_mann Senior Member

    Joined:
    Sep 3, 2020
    3,203
    1,337
    0
    Location:
    NJ-USA
    Vehicle:
    2006 Prius
    Model:
    Four
    If the sound seems to come from under the rear of the car, that might be the leak detection pump running a test on the EVAPorative emissions system.

    Posted via the PriusChat mobile app.
     
  7. shumiron

    shumiron Junior Member

    Joined:
    Apr 20, 2007
    8
    1
    0
    Hello everyone. I have listened more carefully and I believe the noise is coming from the High Voltage battery area. I did a 12 V battery check on the display panel and it reads 11.6 volts with car in accessory mode and 14.1 V when Ready.
     
  8. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    that's a bit low