Highlander - Engine Air Filter and Cabin Air Filter DIY for $25

[@njsongwriter]

Actually, you put the new filter in upside down. Where on the Toyota parts did it say the air flow was up? It did not. The word "UP" on the OEM cabin air filter and other Toyota parts does not indicate air flow direction but simply indicates which side goes up when you install those parts. All horizontally mounted cabin air filters with the blower motor mounted below the filter will have downward air flow (including Toyotas & Subarus and Range Rovers), otherwise incoming dirty air would cause dirt to be trapped below the filter and inside the blower. So if your new filter says up next to the arrow then point the arrow up; but if it doesn't say up then point the arrow down in the direction of the air flow which is the industry standard.

[@EATSLEEPJD]

Thank you Jack ! It was so confusing because I saw all the dirt on the top so I know Air is coming down. I did it on the Honda and Toyota both had the arrow up. I wonder if it actually makes a difference with the filter. I will pin your post and go flip both 😅. Thank you.

[@njsongwriter]

@@EATSLEEPJD Well, if you research a little you'll find that it makes a difference. They say the effectiveness of the filter will be diminished and it may need to be changed more frequently. So no big deal especially for those folks who change them before they need to be changed