I changed my air filter today and cleaned the MAF sensor. While everything was apart I realized no one ever talks about the permanent filter inside the air cleaner. It’s not serviceable but after all these years it has to be clogged. Granted it gets air after the regular filter so any contaminants are the tiniest of tiny on the micron level but those will accumulate over time. I tried to remove it but stopped before damaging anything. Back flushing water through it crossed my mind but I don’t have enough time this evening to let it dry completely... It’s definitely DIRTY!
Any thoughts ?

 

Where's this thing located?

 

Water would likely work if it's not sensitive

 

Turn this upside down...

 

I thought so as well just didn't have time tonight to let it dry completely.

 

Ah well if it's not dripping wet you can just run it and the engine will pull air through and dry it off rather quickly. It would act like simple water injection but very short lived with little risk, I still would say let it dry though if there is no pressing need for the car that evening.

 

What year did they start with this? My 01 only has a paper panel filter.

 

I have never flipped that over! I bet some mild detergent (simple green etc) would be a good bet.

Also, for quicker drying, if you have a front loader dryer, some come with a shoe dry attachment rack. Could just set it in there and run a 30min cycle to dry it up nice!

 

drill out those little plastic welds and remove it. Its called a carbon something filter, its for emissions only.

 

More than anything else, it appears a restriction.
How thick is it?
No other function?
Intake noise attenuation?
Support for filter element?

If an activated carbon element, reminds me of early 1980's General Motors emissions air filter housing bases employing thick ring of activated charcoal around the carburetor inlet.


This is not actually an air filter but a ring of activated charcoal that era GM carbureted engines wheezed on.

Vacuous engineering.

 

Its some California emissions garbage. 4runner owners commonly remove it. I am going to remove mine now that I know it's there. More airflow = better

https://www.toyota-4runner.org/gener...on-filter.html

 

Well, at least now we know why it's there...

Copied from a 4Runner forum-
"While normal air filters serve the purpose of removing particulate matter, such as dirt or debris, from the air entering the air intake manifold, the normal air filter provides little help in preventing evaporative emissions from the intake manifold from entering the atmosphere. Such emissions are a particular problem when the engine is turned off and the intake manifold is hot. This source of air pollution has received considerable attention from the federal and state governments with the goal of reducing such emissions.

To that end, the California Air Resources Board (CARB) which effectively sets the maximum air pollution exhaust standards for all motor vehicles sold in the United States, has passed a regulation which requires that a hydrocarbon trap filter be connected in series with the air intake of most motor vehicle internal combustion engines.

Designs of such a hydrocarbon trap air filter has resulted in a flat-panel hydrocarbon trap filter relatively permanently secured to a downstream section of a conventional OEM closed air box, to inhibit tampering, with a conventional flat panel air filter releasably secured to an upstream section of the closed air box.

The carbon trap filter is formed with one or more layers of granulated activated charcoal (GAC) sandwiched between layers of porous material such as plastic netting and/or non-woven unipolyurethene surrounding an open core. The porous filter media and GAC may be confined within a suitable wire mesh to provide structural strength and rigidity."

 

Not sure what year your car is. I don't have this on my '03.

 

i went out to remove mine in my 2004 , but it was already gone. I must have removed it the day I bought the car

 

This a popular discussion topic on the Tundra Owners Forum as well. Pull 'em out seems to be the consensus over there.