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

2011 engine knock at startup, no problem under load

Discussion in 'Gen 3 Prius Main Forum' started by memento84, Jun 13, 2016.

  1. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    Initially thought that this was related to some water in the tank, since it started when the gas dropped to 1 bar (already put some stuff HEET when put the whole tank, did 60miles so far). ODB throws out multiple cylinder missfire (codes 300, 301, 302, 303 etc). It last up to 3 seconds. Sometimes the check engine pops up sometimes it doesnt. there was absolutely no problem under load. does it seem like a fairly common problem ? Intake manifold clogged ?
     
    #1 memento84, Jun 13, 2016
  2. BZzap!

    BZzap! Senior Member

    Joined:
    Jun 13, 2012
    1,607
    877
    0
    Vehicle:
    2012 Prius
    Model:
    Two
    That or seriously clogged up EGR system. How many miles?
     
    #2 BZzap!, Jun 13, 2016
  3. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    150k miles
     
    #3 memento84, Jun 14, 2016
  4. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    this would be egr valve or the egr valve pipe (or both!) ?
     
    #4 memento84, Jun 14, 2016
  5. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    can this be cleaned (valve), or it has to be replaced (new or used?)?
     
    #5 memento84, Jun 14, 2016
  6. BZzap!

    BZzap! Senior Member

    Joined:
    Jun 13, 2012
    1,607
    877
    0
    Vehicle:
    2012 Prius
    Model:
    Two
    Yes and yes. There are YouTube videos on how to clean the transfer pipe. It's not too bad of a job if you are moderately, mechanically inclined.
     
    #6 BZzap!, Jun 14, 2016
  7. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    there is this assemly mounted on EGR switch, both screws seems to be stuck/rust. any trick to loosen them ?
     
    #7 memento84, Jun 15, 2016
  8. BZzap!

    BZzap! Senior Member

    Joined:
    Jun 13, 2012
    1,607
    877
    0
    Vehicle:
    2012 Prius
    Model:
    Two
    Those are probably SS bolts with a shouldered cap that retains the torque in conditions of expanding and contraction. First of all, use a proper socket or wrench to avoid rounding the head of the bolt. Then you need to use a snapping blow to the tool to break it loose. As with any exhaust related fasteners, you always run the chance of snapping the bolt off. Good luck
     
    #8 BZzap!, Jun 15, 2016
  9. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    I thought I would make a small follow up.
    Initially it was a common gen3 problem, cold, rough start, for couple seconds, small hesitation.
    for some reason, I decided to put in 1$ gas treatment. Well, hell descended upon me - rough start, drive, acceleration. It took 4 full tanks to get that out. In the meantime I was so desperate that I cleaned that EGR pipe and put some WD40 to EGR valve body (no immediate effect). After almost a month it slowly came back to normal, and no more rough start! I got my power back...first 2 months and 5500miles. Im not sure what helped.
     
    #9 memento84, Aug 30, 2016
    Raytheeagle and bisco like this.
  10. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,693
    48,944
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    congrats, well done! necessity is a mother.(y)
     
    #10 bisco, Aug 30, 2016
  11. BZzap!

    BZzap! Senior Member

    Joined:
    Jun 13, 2012
    1,607
    877
    0
    Vehicle:
    2012 Prius
    Model:
    Two
    These Atkinson Cycle engines evidently don't like snake oil. How many miles are on your car? There is an extended warranty on the intake system that you might look into.
     
    #11 BZzap!, Aug 30, 2016
  12. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,476
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    How much buildup was in the egr pipe? Have you gotten any lights on the dash?
     
    #12 Raytheeagle, Aug 30, 2016
  13. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    to my surprise, there was maybe 2mm buildup, completely dry. I got the check engine with the typical random cylinder misfire. Havent reset that engine light yet.
     
    #13 memento84, Sep 4, 2016
  14. Raytheeagle

    Raytheeagle Senior Member

    Joined:
    Jul 1, 2016
    11,251
    15,476
    0
    Location:
    Bay Area, California
    Vehicle:
    2019 Prius Prime
    Model:
    Prime Plus
    At 150 k miles, what intake maintenance has been done ( pcv, throttle body, MAF, intake manifold cleaning, etc)? Does it consume oil?
     
    #14 Raytheeagle, Sep 4, 2016
  15. memento84

    memento84 Junior Member

    Joined:
    Jun 8, 2016
    28
    7
    0
    Location:
    Cleveland
    Vehicle:
    2007 Prius
    Model:
    N/A
    165000miles, so my bet is nay : )
     
    #15 memento84, Sep 4, 2016
  16. douglasjre

    douglasjre Senior Member

    Joined:
    Sep 13, 2008
    1,760
    616
    0
    Location:
    Orlando, FL
    Vehicle:
    2010 Prius
    Model:
    ----USA----
    Did it get warmer outside?
     
    #16 douglasjre, Jan 10, 2018
(You must log in or sign up to post here.)