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Engine revving/knocking sound

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by andrewmarse, Feb 22, 2014.

  1. andrewmarse

    andrewmarse Junior Member

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    Location:
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    Vehicle:
    2008 Prius
    I have a 2008 Prius with 106k miles on it. After driving at highway speeds for 20+ miles and then coming to a stop, the engine will rev way up for a few minutes before calming back down. Additionally, in the last 10k miles, it has started making a bit of a knocking sound. This sound happens from slow to medium speeds. The engine is consuming oil and I have been getting it topped off at Jiffy Lube whenever I fill my gas tank. Any ideas on what might be causing these two seemingly disparate, but potentially related, issues? Many thanks.
     
    #1 andrewmarse, Feb 22, 2014
  2. jdcollins5

    jdcollins5 Senior Member

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    Vehicle:
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    III
    The engine revving can come from a high HV battery SOC. If you were going downhill prior to the stop and the SOC reaches 80% then the engine will rev to start MG1 and throw off battery charge to try to get it back down to the 60% range.

    As for the knocking are you checking oil level between fill ups? Your oil level could be getting low.
     
    #2 jdcollins5, Feb 22, 2014
    ThePrius11 likes this.
  3. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Two
    Take a look at the traction battery state of charge on the MFD. If you see that it is showing 8 green bars when this happens, then the reason for the engine revving up is that MG1 is spinning the engine to burn off excessive traction battery SOC.


    A knocking sound usually means that the engine has excessive wear, for example at a crankshaft bearing. That will cause the knocking sound.

    How much oil is the engine consuming per 1,000 miles?
     
    #3 Patrick Wong, Feb 22, 2014
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