Stock Airbox Modification

[SirDigby]

I did a search for this and nothing came up
hello. I have recently purchased a yaris and have been doing some light work to it this weekend. wile I was doing a shifter kit I removed the upper air box/filter cover. I noticed there was a large filter like obstruction that takes up the entire box. the air box has a filter, so there is no need for this restriction.

-I used a flat head screwdriver to break the plastic rivets and removed the "filter."
-After driving the car, I deduced this is a muffler/air baffle as the engine is much more auditable and sounds good. I also noticed the engine enjoyed the added flow and has a little added pep. I plan to buy an AFE soon, I just thought this is a great "free" mod for a new stock car that i'd let people know about.

this filter is not serviceable. I don't know what the plan is at 100,000 miles when it's all plugged up. I guess if the filter is maintained properly, it should get too dirty, eh? idk, but it doesn't need to be there imo, so I ripped it out.

thanks. I can post pictures, but it's pretty self-explanatory.
Digby

[WeeYari]

That is a charcoal filter and is there for purposes of emission control laws. It is not meant to be removed hence the reason it is hard rivoted in place. There are lots of discussion on here centered around this particular filter.


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[SirDigby]

funny. I examined it and there is not any charcoal in it. it seems to be weaved fiberglass/nylon product. i'd say it's a baffle/muffler. it seems to idle more smoothly and run better with it removed. i'm getting my emissions test in a week or two. i'll let you know if anything is out of the norm....

[SirDigby]

I was just looking at it. you're right, there is some little carbon beads or something in there. oh well, we'll see what happens...

[WeeYari]

Without it you will only fail emission test if there is a visual inspection done as part of the test. Tailpipe or OBD emission tests will not fail because it is absent.

Its purpose in life is to prevent fuel vapor from escaping from the engine back out into the environment via the air box.


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[texascolt45]

I took that out on my Tacoma and went to a k&n filter.although it sounded better I gained not 1 bit of mileage or anything.

[SirDigby]

Originally Posted by WeeYari

Without it you will only fail emission test if there is a visual inspection done as part of the test. Tailpipe or OBD emission tests will not fail because it is absent.

Its purpose in life is to prevent fuel vapor from escaping from the engine back out into the environment via the air box.

ok. sounds good. is fuel vapor out the intake an issue? I've never heard of that. sounds like a fire issue.

I've never done an emissions test before, but i'm sure it will "fast pass" or whatever. usually I register my vehicle in a county that has too low of population, but this one is in boulder county which is full of hippies....