charcoal filter removal

I have a 2010 4cyl access cab and saw the charcoal filter removal in the diy/cheap/free mods section. I was thinking of doing this but wanted some opinions on if it is ok for the engine or not. I read that it is there to keep gas fumes from coming out of the truck when it is shut off but is that all it does? And also if it is it's only purpose do these trucks actually leak gas fumes without it or is it just something they are putting on these days to keep the eco-nuts happy?

It seems like a decent mod for the 4cyl but wanted to get some opinions before I go tearing my new truck apart.

 

Pretty much every CAI removes it. That should say something.

 

I paired it with a afe pro dry s filter ans LOVE it!

 

When you let gas sit, some fumes go into the atmosphere. The Charcoal filter will capture this, and circulate it back.
I don't know much about Charcoal filters on our trucks, but I see no reason why you would need to take it off? I'm also under the assumption it will throw a code if you take it out?

I would say, just leave it on. If it ain't broken, don't fix it.

 

Just a thought?............In removing that filter will it pass the emissions test?............

 

Yeah, I was thinking the same thing.
I'm sure it won't here in CA, that's for sure.....

 

It definitely did not throw a code on my truck in the 3 years it has been removed.

I don't really see a big need to remove it, honestly. A couple folks have done airflow tests on it and with the charcoal filter there's plenty of air for the engine.

However, the fact remains, most CAI's delete it.

 

Unless they do a visual it wont pass otherwise it should because removing it throws no code. I am pretty sure this filter isnt for fumes from the gas rather than the exhaust emissions that flow from the intake valves on the exhaust motion of the piston. The intake valves are opened before the piston hits tdc on the exhaust stroke which allows some combusted a/f ratio to escape through the intake, as much or little as it may be.

 

The removal helps more on the 4 bangers is what I'm hearing...

 

i live in Cali. I removed it. i didnt see much increase but when removing it changing exhaust and switching everything to synthetic i got about a 5mpg increase...and it feels better to the butt dyno...

No check engine light, no problems. Many people in cali have dont it and if you save it you can just pop it back in if you want/need too.

 

intake valve better not open during exhaust stroke... that would = exhaust in intake/ backfire/ piston damage if interference engine

usually the intake valve opens after tdc when the stroke becomes the next intake stroke... even if the intake valve was to open before tdc when the piston came back down it would draw it back in way before it reached the filter. carbon from the exhaust would also show in the intake.

the activated carbon filter absorbs remaining fuel when engine is shut off.

 

I didnt know that about the filter being there for that purpose intersting thank you. But ya there is a slighty vavle overlap. The intake vavles open so close to tdc but it opens nonetheless, im not sure exactly how close though

 

I know there is an exhaust valve overlap on the intake stroke. But i have never heard of intake valve overlap. As the piston comes down the exhaust valve is still slightly open thus the need for backpressure so some the air/fuel from the intake stroke does not continue into the exhaust and you wind up with less fuel/air on the compression stroke.

I could be wrong... wouldnt be the first time lol

Back on topic... I see no possible issues with removing the secondary filter. I only see benefits in fuel mileage and power...

 

thanks for the responses. Im in ny and have no plans to move to cali so im not too worried about emissions tests. And yes, I have read that most people see improvements on the 4cyl, not the 6cyl. I have a 4cyl so im interested in doing it. I just wanted to make sure it wont damage my engine over time or, call it a stupid thought but actually allow gas fumes to leak out and make the truck smell like gas or something.

 

it wont make your truck smell like gas

 

lol good. so to sum this up this charcoal filter is only to make the eco-nuts happy and serves no useful purpose on our trucks?

 

BINGO!!!

 

There is an overlap for both valves

http://www.howstuffworks.com/camshaft.htm

And I think I will remove my charcoal filter. even if the restriction is 0.01%, there is no reason I would leave it there... (?)

 

I removed it when I put in my AFE pro dry. It's there for emissions, but I don't want it there. If you live in CA don't do it. Anywhere else do it if you want - seems to make little difference either way.