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Prius engine slightly stumbles..

Discussion in 'Gen 3 Prius Main Forum' started by Rob Stone, Feb 11, 2019.

  1. Rob Stone

    Rob Stone Junior Member

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  2. Rob Stone

    Rob Stone Junior Member

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    Here is a video of the EGR tubing conditions. The tubing is clear but there is oily deposits inside and the intake manifold has oily deposits.

     
  3. Mendel Leisk

    Mendel Leisk Senior Member

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    They don't look too bad. 120K (or 12 years) was the spec.

    2010 Prius Maintenance Schedule (US).jpg
     

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    #43 Mendel Leisk, Feb 17, 2019
    Last edited: Feb 17, 2019
  4. douglasjre

    douglasjre Senior Member

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    Rob have u found the cause yet? We have a Prius w same issue. We have the misfire on cyl 4, moved plug coil pack and injector, compression tested and still cyl 4.
     
  5. Mendel Leisk

    Mendel Leisk Senior Member

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    What was the readings of the compression test?

    If I've got this right: #4 piston is last in line on driver's side? This is the side EGR gasses enter.
     
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  6. Rob Stone

    Rob Stone Junior Member

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    Test drove it just now, it feels like the stumbling issue improved.

    Your issue sounds like a mechanical problem that is unique to that cylinder. Compression testing is in order?
     
  7. douglasjre

    douglasjre Senior Member

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    180 all cylinders
     
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  8. douglasjre

    douglasjre Senior Member

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    Why does it sound like a mechanical problem?
     
  9. Rob Stone

    Rob Stone Junior Member

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    If you moved the plug and coil to a different cylinder and the cylinder remained the same, the issue is with the cylinder?
     
  10. douglasjre

    douglasjre Senior Member

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    What diagnostic procedure would I use to find it?
     
  11. Rob Stone

    Rob Stone Junior Member

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    The wiring harness for cylinder 4 could have issue along with module that sends signal to that coil. So it still could be electrical problem, after I thought about it. A grounded test spark plug might show loss of spark...
     
  12. douglasjre

    douglasjre Senior Member

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    Where r the modules? I am now noticing the problem exists only after engine warmup.
     
  13. litesong

    litesong Active Member

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    Since you live in Orlando, Fl., where there a plenty of E0 stations, I'd try some E0 gas before any mechanical or electrical solutions. Go to pure-gas.org for a bunch of E0 station addresses. Many WAWA stations.
     
  14. douglasjre

    douglasjre Senior Member

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    Cleaning the stuck EGR fixed the problem
     
  15. ASRDogman

    ASRDogman Senior Member

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    Did you clean the EGR Cooler also? Intake?