Engine Air Filter Box has Built in Filter (1 Viewer)

[TeCKis300]

Doing the 100k maintenance on my LX, and finally noticed there is an integrated and built in filter in the engine airbox cover! It's built into the upper lid, and plastic riveted so it's not meant to be changed.

First time I've ever seen this in an OEM vehicle? I can't see it being a tighter weave than the primary, changeable filter. So it's probably meant as insurance for those that test fate and run without a filter? Could also be meant as a guide for more laminar airflow across the MAF sensor behind it. Or could be a sound buffer to isolate intake noise.

I did try clean it by using compressed air. Narry any dust and dirt, so it's squeaky clean.

This is on my LX570. Do LC's have this?

 

[Tommy Dwyer]

Doing the 100k maintenance on my LX, and finally noticed there is an integrated and built in filter in the engine airbox cover! It's built into the upper lid, and plastic riveted so it's not meant to be changed.

First time I've ever seen this in an OEM vehicle? I can't see it being a tighter weave than the primary, changeable filter. So it's probably meant as insurance for those that test fate and run without a filter? Could also be meant as a guide for more laminar airflow across the MAF sensor behind it. Or could be a sound buffer to isolate intake noise.

I did try clean it by using compressed air. Narry any dust and dirt, so it's squeaky clean.

This is on my LX570. Do LC's have this?

View attachment 1816774

2010 LC here, and mine has it. Eight years old and still clean!

 

[TimCFJ40]

2nd Gen Tacomas have the same. I've read that some people removed them and noticed no gains. Since it's downstream of your replaceable filter element it should be pretty clean, and is likely there in case of catastrophic primary filter failure.

 

[gaijin]

Yes, LC's have it, too.

It's an anti-pollution measure - stops gas fumes from venting to atmosphere when engine is stopped.

HTH

 

[Taco2Cruiser]

^^^ Yep!

I second what @gaijin said... dead on correct.

They have been on every 2.7L, 4.0L, 4.6L, and 5.7L since 2003.

I know some cut it out for more "airflow," mostly Tacoma and FJ guys. Yet those people are also ones that think cotton gauze filters are good...

Leave it in, the throttle body is absolutely the limiting factor of the intake design. @4gotalot did some testing, and found that when taping off up to 75% of the filter, the CFM into the motor was still the exact same as a completely free intake.

 

[TeCKis300]

Interesting! Learned something today. Thanks for the input!

 

[04UZJ100]

I’ll pull mine out. It’s a hydrocarbon filter that does nothing but restrict more air.

 

[Taco2Cruiser]

I’ll pull mine out. It’s a hydrocarbon filter that does nothing but restrict more air.

It doesn’t restrict air into the motor. Read below (or above). It’s there for a reason, to help lower pollution. Which is a good thing.

Leave it in, the throttle body is absolutely the limiting factor of the intake design. @4gotalot did some testing, and found that when taping off up to 75% of the filter, the CFM into the motor was still the exact same as a completely free intake.

 

[04UZJ100]

It doesn’t restrict air into the motor. Read below (or above). It’s there for a reason, to help lower pollution. Which is a good thing.

Modern engines are shut off by the injectors. There should be no hydrocarbon vapors emitting from the intake.

 

[Taco2Cruiser]

Modern engines are shut off by the injectors. There should be no hydrocarbon vapors emitting from the intake.

While true, the injector itself is not the issue.

Since we have port injection, there is a moment when an air fuel mix is getting sucked into the intake valves... annnnddd... the engine shuts down.

Now you have an unburned air fuel mix hanging out, with two open valves that lead strait to the air box.

Now if that’s not enough facts, I’m going to assume that Toyota, has more engineering and financial prowess than you.

Do you really think an automaker, is going to waste even a cent on something, that when added to tens of millions of cars, resulting in millions of dollars of lost profits for something that “doesn’t do anything?”

I mean, you’re literally assuming that Toyota is good enough to build a 100% isolated engine (that runs off of far more air than fuel), but then simultaneously assuming that Toyota is dumb enough to not realize they don’t need a charcoal filter on the air box?

I’m hate being condescending, even though I am falling to that right now, and I apologize for that.

But I don’t apologize for not letting false statements slide. This is the number one problem with anything automotive related. Assuming things are better without any base of reference.

Now to try and be the fun loving Taco again, here’s a video from Donut that is just enjoyable to watch.

 

[04UZJ100]

While true, the injector itself is not the issue.

Since we have port injection, there is a moment when an air fuel mix is getting sucked into the intake valves... annnnddd... the engine shuts down.

Now you have an unburned air fuel mix hanging out, with two open valves that lead strait to the air box.

Now if that’s not enough facts, I’m going to assume that Toyota, has more engineering and financial prowess than you.

Do you really think an automaker, is going to waste even a cent on something, that when added to tens of millions of cars, resulting in millions of dollars of lost profits for something that “doesn’t do anything?”

I mean, you’re literally assuming that Toyota is good enough to build a 100% isolated engine (that runs off of far more air than fuel), but then simultaneously assuming that Toyota is dumb enough to not realize they don’t need a charcoal filter on the air box?

I’m hate being condescending, even though I am falling to that right now, and I apologize for that.

But I don’t apologize for not letting false statements slide. This is the number one problem with anything automotive related. Assuming things are better without any base of reference.

It’s an EPA mandate. Simple as that.

Opening your lawnmower gas tank releases more hydrocarbons.

I ripped the filter out of my 4Runner 175k gap.

If you’re going to preach green, you’re driving the wrong car.

 

[Taco2Cruiser]

It’s an EPA mandate. Simple as that.

Yes it’s an EPA mandate, cars can only release a certain amount of hydrocarbons while not operating. Which is why that carbon filter is there. That’s what we’re talking about.

You’re changing up your argument. You said it doesn’t do anything, it does.

Then you say it’s an EPA mandate, umm yeah. Then you mention lawn mowers, which is not regulated the same way as passenger cars, so what doesn’t that have to do with anything we’ve been talking about?

Taking your filter out means nothing other than you did something.

Then the green comment. Listen guy, i’ve been driving 13 mpg 4x4s since I could drive, got no problem with that. But again, that’s not what we’re talking about. We’re talking about “what does this thing in my air box do?”

You said nothing, which is wrong. It does do something. Just because you don’t like it, doesn’t make it any less true.

 

[04UZJ100]

Yes it’s an EPA mandate, cars can only release a certain amount of hydrocarbons while not operating. Which is why that carbon filter is there. That’s what we’re talking about.

You’re changing up your argument. You said it doesn’t do anything, it does.

Then you say it’s an EPA mandate, umm yeah. Then you mention lawn mowers, which is not regulated the same way as passenger cars, so what doesn’t that have to do with anything we’ve been talking about?

Taking your filter out means nothing other than you did something.

Then the green comment. Listen guy, i’ve been driving 13 mpg 4x4s since I could drive, got no problem with that. But again, that’s not what we’re talking about. We’re talking about “what does this thing in my air box do?”

You said nothing, which is wrong. It does do something. Just because you don’t like it, doesn’t make it any less true.

Man I struck a chord.

 

[bloc]

Modern engines are shut off by the injectors. There should be no hydrocarbon vapors emitting from the intake.

Then there’s that whole pcv thing

 

[Taco2Cruiser]

Man I struck a chord.

The cord of TRUTH!!

 

[abuck99]

The cord of TRUTH!!
View attachment 1817569

Ahh the Macho Man- one of my favorites.

 

[Markuson]

Man I struck a chord.

If “ridiculous” is a chord...
...then ya, you sho-nuff struck it, mate.



All I saw was a good dude giving a good answer to a good question.