Carbon (air) filter

2003 Tundra 4.7L 4x4 access cab with 120,000 miles.

Regarding the carbon filter - the secondary filter after the main engine air filter:

I’ve been trying to do some research, and still have some questions. First, my understandings:

1. The filter is to absorb fumes flowing back out when the engine is off.
2. It is not serviceable and in theory it seems like we don’t need to worry about it, ever.
3. Plenty of people just pull it out and forget about it.

So my questions are:

1. I’m not a chemist, but it seems like a substance that absorbs a chemical would, over time, become saturated and useless. (My working theory is that when the engine is running, air passing *into* the engine cleans out the fuel fumes, but see point #2…)
2. The previous owner and I have been good about changing the air filter, and as far as I can tell everything downstream of it looks pretty damn clean. However, after 17 years in the dusty desert, I feel like that secondary carbon filter has to be pretty clogged up?
3. With regards to simply removing it, I assume that the engineers who designed the system took the filter and its resulting airflow restriction into account, so I would think that removing it would be detrimental? Or do the subsequent sensors - MAF, O2, etc, take the change into account over a few drive cycles?

Anything else I should know, think about? Clean it? Blow it out? Remove it? Put everything back and forget about it?

Moderately related question: in writing this it occurs to me that my entire air intake area seems much cleaner than it should, even on the outside / intake side of the engine air filter.

I do quite a bit of off-road driving, often, unfortunately, behind somebody else, on the very dusty roads of Arizona and Utah. I drive in a lot of clouds of dust, but that air filter box looks nearly clean enough to eat out of. Is that normal? Makes me think I’ll check the intake area tomorrow in the light.

(At least my air box isn’t full of pinecones like that one thread I saw!)

 

Just keep it on. Its not hurting anything or causing problems.

 

It's part of your fuel evaporation system, and it's not harming performance.

 

(Finally added a photo for future researchers' clarity.)

Thanks for the answers, I'll leave it alone!

 

I looked a few months ago on my 2002 and it doesn’t seem to have one. I think the 00-02 do not have these filters. Someone confirm. I swear I read it in a manual for a 2003 that they introduced it that year.

Anyhow, its on the clean side of the actual air filter so it shouldn’t be dirty unless you have major problems.

 

My 2002 doesn't have one, never did.

 

I'm not sure but when I went to remove mine it was already gone. I just assumed the previous owner took it out.

@NomadicFrog as for leaving it in vs taking it out. I have my doubts than any filter can last a "lifetime".

I don't think one is going to see any consequences for leaving it in or taking it out. I really don't think it matters. I think we had a few people that swore they could tell a difference when they removed it. That seems unlikely but maybe they did.

 

Yeah, things on the clean side of mine look pretty good, and I'm not worried per se, but...

Yeah, that. Anyhow, I'm leaving it alone for now. I don't see anyone saying one must do something about it, and a lot of reputable people saying don't mess with it.

And I have other issues. I just cleaned the MAF sensor and the throttle body (with the appropriate CRC cleaners for each), reassembled everything, and...

1. Engine didn't want to start first try.
2. Engine fired right up on second crank.
3. Check Engine Light immediately came on. Code P0113 "Intake Air Temperature Sensor 1 Circuit High Bank 1"
4. Argh

I let it run for a bit, cleared the code, and checked it again, no code. Shut it down until I could research further. Hope I didn't mess something up.

Also the OBD reader listed 4 "Readiness Monitors" as "incomplete":

• Catalyst monitoring
• Evaporative system
• Oxygen sensor
• Oxygen sensor heat

I...hope those are just because everything needed to get up to temp? <insert sweating nervous emoji>

 

I had a check engine light come on once after cleaning the MAF. I cleared it and never came back. Next time you clean the MAF, disconnect the battery first. That's what I do now.

 

I removed the MAF sensor entirely, sprayed it from various angles, let it dry, and replaced it.

 

When I got my 03, it was on there. I had issues with it running and after cleaning the MAF & TB, I removed this and the K&N and just tossed in an OEM filter.

Didn't run when I had it so I don't know if it changed but everything runs fine without it.

 

I put a sock on my hand and gently caress the MAF whilst giving it a gentle spray. Its always hooked up and battery connected. I shake it after giving it a few shots to dry it. Never any problems ever. Hope the best Nomadic!

 

One of the first things I ripped out. But looking back, I would leave it now. It’s not very restrictive at all. Just smog shit. And I doubt it’ll ever get dirty enough to need to be addressed.

 

I ripped mine out long ago, just out of fear that it could rot and fall apart and bits could make their way through my throttle body. It's as flimsy as pantyhose and doesn't seem to have a tangible benefit. Where I lived at the time Summer days were 105+ and worse in my driveway, hot weather can be brutal.

 

Ditto.