Dual air filter - removing one of the air filters

[OilUzer]

We have a 2014 Hyundai Tuscon 2.4 L DI engine

The car has a dual air filter (pzev - partial zero emission stuff ...)
i can access one of the air filters but there is another air filter on top of the other filter and is glued in to the top of the plastic canister.
was wondering if i can take it off (break off the little plastic things holding it in) and remove the second air filter.
i was told it is for zero emission and many cars (like all our other cars) don't have the second air filter!

basically i wanted to see what is on top of the 2nd air filter, for example oil from pcv and crankcase, etc. but this second air filter does not allow access. who knows it may even be nasty and dirty on top and blocking the air flow but I can never get to it.

do you have any experience with dual air filter and pros and cons of removing it.
Thanks

 

[Nick1994]

I read the title before clicking and thought "It's gonna be about a Hyundai". [censored] I'm good.

My car has it too. I think the Hyundai engineers are smarter than me, so I'm not going to mess with it.

 

[Kira]

To me the OP was a little lacking in description.

 

[barkingspider]

My daughter’s Camry had something similar. I broke the plastic tabs and removed it over 2 years ago. Car runs fine

 

[supton]

I thought dual air filters was a big truck or off road equipment thing. A pre-filter to get the big stuff, like dust or whatever might be floating in the air. The real filter is downstream. Reason being, the pre-filter can be "less good" because any filter would just plug up; so make it cheaper and/or easier to clean/replace.

not sure why they'd need a better air filter on a PZEV? I mean, clean air is clean air. Unless if residue dust could be turned into PM? thus meaning they need all the more filtration?

 

[pandus13]

OP,

Maybe register to the hyundai forums and post the question there?

 

[BurrWinder]

That's likely not a "filter".. it is most likely a carbon Adsorber - ( yes, I spelled that correctly ) It is used to absorb fuel vapors that exist in the air filter housing ( after engine is shut off ) and keep them from floating away, causing emission issues. That is why it's not removable, "sposta be in there" and it isn't normally required to be replaced in the normal life of the vehicle. This usually requires filter housing replacement, if needed, to replace it - Not usually a need unless damaged. 1st filter is the filter, this part exists as described and not for filtering, technically. Other vehicles, such as some Trailblazers and others use this design, as well. Works just like a carbon canister, but "open faced" carbon to solve another problem. Vapors are drawn off in normal use anytime engine is running.

BurrWinder

 

[circuitsmith]

The second air filter has activated charcoal to catch any wisp of raw gas that makes its way up the intake manifold when the engine is stopped.
Then, when the engine is running, fresh air coming in (somewhat) clears the charcoal of gas.
My '06 Matrix had one too...until I yanked it out.

 

[ARB1977]

I kept mine in my Tacoma. Doesn’t hurt anything.

 

[OilUzer]

Originally Posted By: Kira
To me the OP was a little lacking in description.


when you open/unclip the air filter box/housing, There is a removable air filter laying down like most cars ...
However in the air filter cover (the part you unclip to access the air filter) you typically (as in all other cars I currently own from 1997 to 2016) see a hose going from air filter cap to intake. in this car I see another filter glued in there (i.e. not removable unless I break a few pins).



Originally Posted By: circuitsmith
The second air filter has activated charcoal to catch any wisp of raw gas that makes its way up the intake manifold when the engine is stopped.
Then, when the engine is running, fresh air coming in (somewhat) clears the charcoal of gas.
My '06 Matrix had one too...until I yanked it out.


Originally Posted By: BurrWinder
That's likely not a "filter".. it is most likely a carbon Adsorber - ( yes, I spelled that correctly ) It is used to absorb fuel vapors that exist in the air filter housing ( after engine is shut off ) and keep them from floating away, causing emission issues. That is why it's not removable, "sposta be in there" and it isn't normally required to be replaced in the normal life of the vehicle. This usually requires filter housing replacement, if needed, to replace it - Not usually a need unless damaged. 1st filter is the filter, this part exists as described and not for filtering, technically. Other vehicles, such as some Trailblazers and others use this design, as well. Works just like a carbon canister, but "open faced" carbon to solve another problem. Vapors are drawn off in normal use anytime engine is running.

BurrWinder


Thanks for the replies everyone, it make sense for it to be a carbon filter to prevent fuel/vapors from exiting when the car is shut off.

Having said that, sometimes if you have issues with the pcv or vacuum you may find oil film on top of the air filter.
With this car I cannot check for that unless I break the thing and remove the second air filter (it may? affect the warranty if I ever end up in dealership). I have some issues with oil film near oil cap and pcv (I have a post under oil forum) and was going to check the air filer and see if I can find anything wrong. I will edit and add the link to my other post.

edit:

Oil Film on engine cover