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

Cabin Air Filter Question

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by darkgiant, Jan 25, 2018.

  1. darkgiant

    darkgiant Member

    Joined:
    Jan 16, 2013
    287
    42
    2
    Location:
    Seattle
    Vehicle:
    2013 Prius
    Model:
    II
    This is a silly question but figured I'd ask. I just got this Cabin Air Filter from Amazon (won't let me link, but it is a "EPAuto CP285" Filter:


    I am thrown off by the arrow (when inserting the filter), and now I am lost because the previous air filter that I am replacing (OEM variant) had a different direction arrow. Which direction am I supposed to put this filter based on the arrow, up or down? Here is a screenshot of how the arrows and placement look like (also should note, this image was not taken by me, just a screenshot of the images provided by an Amazon reviewer):

    Screen Shot 2018-01-25 at 12.54.58 PM.png Screen Shot 2018-01-25 at 12.57.14 PM.png
     
  2. RRxing

    RRxing Senior Member

    Joined:
    Jul 7, 2009
    2,518
    1,790
    0
    Location:
    NEPA
    Vehicle:
    Other Hybrid
    Model:
    Limited
    Air flow goes from top to bottom. Think about it - how could the filter retain debris if the air flow was from bottom to top?
     
    Tande and dubit like this.
  3. ILuvMyPriusToo

    ILuvMyPriusToo Senior Member

    Joined:
    Dec 4, 2014
    778
    514
    0
    Location:
    Outside Philly, PA
    Vehicle:
    2009 Prius
    Model:
    II
    Would be self cleaning! (y)
     
    RRxing likes this.
  4. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,683
    48,934
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    arrows point down.
    doesn't the engine air filter collect debris on the bottom?
     
    Mendel Leisk likes this.
  5. darkgiant

    darkgiant Member

    Joined:
    Jan 16, 2013
    287
    42
    2
    Location:
    Seattle
    Vehicle:
    2013 Prius
    Model:
    II
    It is certainly a silly question, for such a menial and simple task, but I figured it was worth asking as when I was browsing for cabin air filters, many of them had different directions for the arrows, compared to OEM. But just to clarify, in this filter, the darker area should always then face, where as the lighter portion faces up, correct? I saw some filters where the opposite was the case, or some that were equal in shade for both sides.
     
  6. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,683
    48,934
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    the role is, the oem filter says up or down with the arrows, so it's hard to make the same mistake as aftermarket.
     
  7. Grit

    Grit Senior Member

    Joined:
    Aug 22, 2017
    6,109
    4,038
    1
    Location:
    Wilkes Land
    Vehicle:
    2012 Prius
    Model:
    Four
    Bought some non oem Toyota cab filters and the arrow indicated orientation "this side up" rather than arrow mean air flow
     
  8. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,639
    38,199
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Maybe it doesn't matter which side is up at the start, not sure though. If that were the case, then I'd think the main criteria would be to not use it with one side up for a while, then flip it.
     
    CR94 likes this.
  9. Jimi1976

    Jimi1976 Active Member

    Joined:
    May 15, 2013
    242
    124
    0
    Location:
    Denver, CO
    Vehicle:
    2010 Prius
    Model:
    III
    The system sucks air from inside your car, pumps out through the vents. Follow the flow arrow based on that...that’s all.
    Up/down....is irrelevant
     
  10. dubit

    dubit Senior Member

    Joined:
    Dec 3, 2016
    850
    538
    23
    Location:
    Indiana
    Vehicle:
    2016 Prius c
    Model:
    Two
    Anyone else like me and just throw them away - and NOT replace them at all?
     
  11. RRxing

    RRxing Senior Member

    Joined:
    Jul 7, 2009
    2,518
    1,790
    0
    Location:
    NEPA
    Vehicle:
    Other Hybrid
    Model:
    Limited
    The bottom line is - as long as the filter fits properly without being forced, it really doesn't matter which side is "up."
     
  12. dubit

    dubit Senior Member

    Joined:
    Dec 3, 2016
    850
    538
    23
    Location:
    Indiana
    Vehicle:
    2016 Prius c
    Model:
    Two
  13. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    54,639
    38,199
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    I'm at 73,000 kms on the original cabin filter, just vacuum it out every year or two. It's getting on though I think. The engine air filter: same story, but it looks really good, near-new.
     
    Lightning Racer and dubit like this.
  14. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,642
    1,134
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    Confusion is inevitable when some manufacturers use an arrow to show flow direction, but one perversely uses a similar arrrow to show which way is upwards, which happens to be the opposite.
     
    dpframing likes this.
  15. RRxing

    RRxing Senior Member

    Joined:
    Jul 7, 2009
    2,518
    1,790
    0
    Location:
    NEPA
    Vehicle:
    Other Hybrid
    Model:
    Limited
    Hope these help... (from the 2010 New Car Features)

    Screen Shot 2018-01-28 at 7.35.40 AM.png

    Screen Shot 2018-01-28 at 7.36.17 AM.png
     
  16. El Dobro

    El Dobro A Member

    Joined:
    Jul 12, 2011
    6,972
    3,209
    1
    Location:
    NJ
    Vehicle:
    Other Electric Vehicle
    Model:
    N/A
    The only difference I can see it making is if one side is constructed differently, like a furnace filter is. The main thing is for me is that I prefer the carbon impregnated filters.
     
    Mendel Leisk likes this.
  17. Rebound

    Rebound Senior Member

    Joined:
    Mar 11, 2010
    3,961
    2,609
    0
    Location:
    Portland, OR
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    The arrow does not matter EXCEPT when you remove the filter for cleaning. If you put the filter back in, the orientation MUST be the same or you’ll blow dirt all over your interior.
     
    Lightning Racer and Mendel Leisk like this.
  18. darkgiant

    darkgiant Member

    Joined:
    Jan 16, 2013
    287
    42
    2
    Location:
    Seattle
    Vehicle:
    2013 Prius
    Model:
    II
    I inserted the filter with the darker (blacker side) facing the fan (hence, bottom) and the lighter side facing the upper/top side. Thanks for the discussion. I am not even sure if this filter is any good, or if any of this charcoal+baking soda stuff works, but figured it'd be nice to try since it was super cheap.
     
  19. MikeDee

    MikeDee Senior Member

    Joined:
    May 9, 2013
    1,534
    582
    0
    Location:
    San Francisco Bay Area
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Yes, but the filter is infused with charcoal, and that gets used up over time.
     
    Mendel Leisk likes this.
  20. CR94

    CR94 Senior Member

    Joined:
    Dec 2, 2014
    2,642
    1,134
    0
    Location:
    Northwestern S.C.
    Vehicle:
    2011 Prius
    Model:
    Two
    ... and more importantly, clog (at least partially) your heater core or evaporator with "dirt."