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Cabin Air Filter Question

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

  1. darkgiant

    darkgiant Member

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    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

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    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?
     
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  3. ILuvMyPriusToo

    ILuvMyPriusToo Senior Member

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    Would be self cleaning! (y)
     
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  4. bisco

    bisco cookie crumbler

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    arrows point down.
    doesn't the engine air filter collect debris on the bottom?
     
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  5. darkgiant

    darkgiant Member

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    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

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    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

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    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 EGR Fanatic

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    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.
     
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  9. Jimi1976

    Jimi1976 Active Member

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    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

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    Anyone else like me and just throw them away - and NOT replace them at all?
     
  11. RRxing

    RRxing Senior Member

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    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

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  13. Mendel Leisk

    Mendel Leisk EGR Fanatic

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    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.
     
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  14. CR94

    CR94 Senior Member

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    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.
     
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  15. RRxing

    RRxing Senior Member

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    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

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    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.
     
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  17. Rebound

    Rebound Senior Member

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    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.
     
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  18. darkgiant

    darkgiant Member

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    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

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    Yes, but the filter is infused with charcoal, and that gets used up over time.
     
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  20. CR94

    CR94 Senior Member

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    ... and more importantly, clog (at least partially) your heater core or evaporator with "dirt."