What purpose does this serve?
 

excuse the picture quality, but is this some type of resonator? what's the difference with or without it? what happens if i take it off and fill the hole?

i have no clue what they are for but i do know my 08 dosnt have it or the one behind it the nipple like parts are there on the airtube but they were never cut out on the inside from the factory if you wanted to get rid of them you could get a intake tube from a 08 or since yours is a 03 get a cold air intake i cant get a cold air intake because they swapped maf styles in 04 and no one has came out with a kit for the new ones

I think it has something to do with controlling the noise of the air entering the engine..

yeah it cant possibly have anything to do wit anything but noise, no holes, no wires connected t it.

the thing behind is that exhaust gas recirculation thingy right?

i think i'm gonna take it off and see what happens

plug up the holes before you run it or you will pop a check engin light on

You are correct, it is just a silencer.

i will haha i was thinking a stetched out balloon and the clamp would do.

ohkay, do you know how the sound changes? is it a good sound or something weird like a whistle if you take it off?

i have no clue on the sound ive never had another 2.3 to compare it to

i would get somthing better than a ballon to plug it up you may end up making ballon animals in your throttle body

i took expandable rubber plugs and plugged it on my old 01. Its just there to limit intake noise

its there to reduce resonance at a certain RPM.

It's for NOS

i like his thinking haha