Trouble Persists After EGR, Cooler Replacement

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by BrokenOregonPrius, Feb 20, 2020.

  1. BrokenOregonPrius

    BrokenOregonPrius New Member

    Joined:
    Feb 20, 2020
    4
    0
    0
    Location:
    oreon
    Vehicle:
    2010 Prius
    Model:
    N/A
    Hello all,

    Long time lurker, first time poster. I started having trouble with my 2010 Gen 3 Prius about a year ago. The symptoms seemed to match those described her by posters with EGR problems, and indeed my EGR cooler was blocked with carbon. First I tried cleaning the EGR cooler, intake, and valve as described here. I always need the car to get back to work the next day, and I don't think I got it as clean as I should have, so the problem returned about a month ago. (This is a high-mileage car driven about 90miles each weekday).

    This time I replaced the EGR valve and cooler. I bought the cooler new from Toyota and the valve from RockAuto; it is a WVE-brand part.

    The knocking I had experienced under mild load has not stopped. With EGR valve plugged in, the check engine light is off and the car runs poorly; feels like it is going to shake itself apart. With the EGR valve unplugged, the CEL is on yet the car runs perfectly. I am not getting the misfire code from the OBD2 scanner in either case.

    What on earth is going on? And--am I going to hurt anything if I just continue to drive it with the EGR unplugged?
     
  2. FrankB

    FrankB Member

    Joined:
    Dec 12, 2012
    110
    48
    0
    Vehicle:
    2010 Prius
    Model:
    II
    Did you clean the EGR ports in the intake manifold?
     
  3. BrokenOregonPrius

    BrokenOregonPrius New Member

    Joined:
    Feb 20, 2020
    4
    0
    0
    Location:
    oreon
    Vehicle:
    2010 Prius
    Model:
    N/A
    I’m not sure. I scrubbed out the port where the pipe connects, if that’s what you mean. Is there another EGR port to clean besides that?
     
  4. pjksr02

    pjksr02 Member

    Joined:
    Nov 2, 2009
    352
    98
    2
    Location:
    Connecticut
    Vehicle:
    2010 Prius
    Model:
    III
    Just a thought: could a dirty MAP sensor be the cause? With all the oil that gets by the PCV valve, this sensor gets its share, and might be giving the engine control module a false reading.
     
    BrokenOregonPrius likes this.
  5. Mendel Leisk

    Mendel Leisk 'Orrible Oracle

    Joined:
    Oct 17, 2010
    38,336
    27,132
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Yeah. The EGR passage runs right through, splits into 4, they come come out, one per intake port. Watch @NutzAboutBolts videos.
     
  6. BrokenOregonPrius

    BrokenOregonPrius New Member

    Joined:
    Feb 20, 2020
    4
    0
    0
    Location:
    oreon
    Vehicle:
    2010 Prius
    Model:
    N/A
    I’ll try cleaning those ports; removing the intake is easy enough.
     
  7. BrokenOregonPrius

    BrokenOregonPrius New Member

    Joined:
    Feb 20, 2020
    4
    0
    0
    Location:
    oreon
    Vehicle:
    2010 Prius
    Model:
    N/A
    Not to hard to get to...I’ll try cleaning it at the same time I clean the intake ports. Thank you.
     
  8. Mendel Leisk

    Mendel Leisk 'Orrible Oracle

    Joined:
    Oct 17, 2010
    38,336
    27,132
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
  9. Mendel Leisk

    Mendel Leisk 'Orrible Oracle

    Joined:
    Oct 17, 2010
    38,336
    27,132
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    At each "port" on the intake manifold it's the small opening, 1/4" diameter.

    I found a brush designed for cleaning stainless steel drinking straws worked well. Start it in, then add a little shot of brake cleaner, work it.
     
    pjksr02 likes this.
Loading...