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Cabin air filter installation issue

Hey got a new cabin filter to replace since my mom probably never did it… and as expected it was all black and crudy. I also went with a charcoal activated one from FRAM.

Now the issue is, well, I’m not sure really let me explain.

The airflow arrow on the filter should be pointed down since that’s how it goes. But the problem is have to notch the sides of the filter onto the notch that run on each side of the filter tray (picture for reference). Installing it with the arrow flowing down doesn’t fit in those notches because the filter pleates are to fat (picture). But installing it the other way around (arrow going up) it fits perfectly because the side pleates on that side are made to fit (picture)

So I’m at a dead end and not quite sure. Any inputs on this? Car is 2006 Hyundai Tucson by the way.

Knowing the make and model might help. What if you rotated it 90 degrees?

The airflow is from your wiper area towards the footwell, seems like you got this right.

How was the old filter fitted there. Can you put it back in same way you want to put this one in?

Maybe the filter is not the right one.

Honestly, I don’t think if the arrow is pointing the wrong way, it is going to have much effect.

The FRAM filter model is CF10709. The filter the was in the car before has “08790” and ‘2E200A’ on it. Can’t roate any 90 degrees since one side becomes to long.

For the flow, I thought that it goes through the white pleat to filter out object and such and then goes into the charcoal for the odor and doing the opposite might screw it? I can still put the way with arrow pointing down it’s just the sides won’t be perfectly anchored in and there may be like a microscopic gap between the sides.

Why didn’t you get the OEM Hyundai filter for your vehicule? it probably cost a little more than the Fram but it will fit perfectly.

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up or down? i bet it filters just fine if it is “upside” down. its a cabin air filter for a leaky metal box with 4 poorly sealing doors.


I agree with @Cavell - this is about as non-critical as a filter gets. Install it the way it fits the best.

if filter obviously fits ok in opening than it will work. it has to be better than old dirty filter

How many makes and models were made in the 2006 Tuscan lineup?

I agree with Cavelle, charcoal does not care which direction the air is flowing so put it for the best physical fit.

I wanted a charcoal one. OEM isn’t charcoal activated.

Oh yeah huh? Cabin air filter don’t really matter which way?

You logic seems sound OP that the preferred path should be having the air flow exiting the charcoal side of the filter. But in practical terms I doubt it matters enough to worry about. If the one you are using is a little less expensive than the OEM filter, then take advantage of that price difference by changing it a little more frequently. You should be good to go.

I expect you already know that the entire past century of cars (i.e. the 1900’s) had no cabin air filters at all, and that configuration seemed to be ok for most drivers. Any filtering at all is better than that 100 years.

In general. you want the rough/tough looking side toward the cabin. They are made that way so that pieces of the filter element don’t blow into the cabin. I hope that might help. On that theory, the charcoal side does not face the cabin.

The charcoal bed should be downstream of the primary filter media.

The function of the primary filter media is to remove contaminates from the air down to a certain micron.

The function of the charcoal bed is to remove any vapors,odors,etc from the air. It’s not designed to remove particulate.

If the charcoal bed is placed upstream, it’s destroyed from the particulate.


This room air filter costs over $500 and contains “About 15 lbs. of Activated Carbon and Zeolite”:

The probability of the carbon in your cabin filter significantly affecting air quality approaches zero.

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