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

Does my Prius have an EGR system?

Discussion in 'Gen 3 Prius Technical Discussion' started by giora, Sep 13, 2010.

  1. 08PriusXSJ

    08PriusXSJ Junior Member

    Joined:
    Jan 3, 2017
    42
    13
    0
    Location:
    Connecticut
    Vehicle:
    2008 Prius
    Model:
    One
    On the Google image, I found the snapshots of the I/M test screen by other scanners also show that the EGR, Heated catalyst, air are not supported for the Prius. See picture below.[​IMG]
     
  2. m.wynn

    m.wynn Senior Member

    Joined:
    Oct 24, 2013
    684
    1,226
    0
    Location:
    Queensbury, NY
    Vehicle:
    2014 Prius
    Model:
    Three
    Correct, well sort of. Gen 2 Prius has no external EGR and OBD sensor. It uses "internal EGR," where the ECU dictates valve overlap to the variable valve timing system at typical EGR required engine loads. This allows back-flow of exhaust gas into the combustion chamber in a maintenance free package. Of course Toyota went external EGR for Gen 3 and did a marginal job with it. It's a very common trouble area for Gen 3 with moderate to high mileage, becoming partially to fully clogged with sludge and causing performance issues.
     
    anonymous and Raytheeagle like this.
  3. DonDNH

    DonDNH Senior Member

    Joined:
    Feb 3, 2004
    1,711
    654
    0
    Location:
    Nashua, NH
    Vehicle:
    2016 Prius
    Model:
    Four Touring
    Maybe no longer illegal. I've seen some US Spec Audis and MBs recently with rear fog lights.
     
  4. 08PriusXSJ

    08PriusXSJ Junior Member

    Joined:
    Jan 3, 2017
    42
    13
    0
    Location:
    Connecticut
    Vehicle:
    2008 Prius
    Model:
    One
    Thanks. it seems that the scanner was telling the truth so I don't need to worry about this one for the coming car emission:)
     
  5. Figster10

    Figster10 Member

    Joined:
    Jan 19, 2019
    207
    61
    0
    Location:
    Sacramento
    Vehicle:
    2007 Prius
    Model:
    Two
    Even knowing the egr valve is internal on gen 2 what is the fix for burning oil if we can't actually physically clean the pipes or can we? I'm being told to use 0-20 for oil for 10-40 but can anyone confirm this?
     
  6. m.wynn

    m.wynn Senior Member

    Joined:
    Oct 24, 2013
    684
    1,226
    0
    Location:
    Queensbury, NY
    Vehicle:
    2014 Prius
    Model:
    Three
    The EGR system on Gen 2 is virtual, with software controlling valve timing to simulate a physical EGR. There is no EGR valve or "pipes" to clean on your '07. To my comprehension, you are implying that cleaning EGR is the fix for oil burning, but even with regard to turd gen and it's external EGR, this is not the case. Engine tear down and cleaning to free up or replacing the coked oil control rings entirely and clearing the clogged oil return holes in the pistons is the only proper fix. Piston soaks and various engine oil additives can offer some control over the oil burning situation worsening, and even yield degrees of improvement, but these modalities are merely damage control.
     
  7. mikefocke

    mikefocke Prius v Three 2012, Avalon 2011

    Joined:
    Nov 3, 2012
    3,760
    1,680
    0
    Location:
    Sanford, NC
    Vehicle:
    Other Hybrid
    Model:
    Limited
    Not on 4 cars I have owned, There was a single special rear fog light you activated. Common question on Porsche forums is why isn't the other fog light working. Only one to distinguish it from the 2 brake lights. I forget what color it was.
     
  8. Figster10

    Figster10 Member

    Joined:
    Jan 19, 2019
    207
    61
    0
    Location:
    Sacramento
    Vehicle:
    2007 Prius
    Model:
    Two
    I've heard from many this typically does help a lot but of course every situation is different and still requires close monitoring the more we drive these cars. I just wanted to make sure I wasn't missing anything in attempting to do damage control when I start with the work.
    Thanks again and still more reason to crown the prius best car ever lol
     
  9. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,913
    16,216
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    Hmm, the valve timing arrangement that keeps being called "internal EGR" or "virtual EGR" here is common to all generations of Prius engines ... it's that timing that provides the Atkinson cycle effect, allowing the engine's expansion ratio to be higher than its compression ratio. I'm not convinced it recirculates very much exhaust gas; what it does is keep the intake valve open a bit later so that some of the unburned, intake charge is returned to the intake manifold rather than being compressed.

    So when EGR was added in the third generation, it really was because their design now called for EGR, so they added it.
     
    Cosmo Tigato and Figster10 like this.
  10. Rossini2

    Rossini2 New Member

    Joined:
    Jan 29, 2020
    5
    0
    0
    Location:
    London
    Vehicle:
    2004 Prius
    Model:
    II
    I have same noice but not too much the code showing p0303 what will the problem the egr or plugs.
     
  11. AKoffgrid

    AKoffgrid New Member

    Joined:
    Jul 28, 2023
    13
    5
    0
    Location:
    Alaska interior
    Vehicle:
    2007 Prius
    Model:
    Touring
    So, with symptoms( vibration at low idle) much like a gen 3 egr with dirty egr line and pipes, but on a gen 2, are there any places to he looking next?