What is this thing?
 

I'm installing an AEM short ram on my 96 accord ex. It's all very simple, just like it should be. But there was a pipe on the underside of the stock intake duct that led back towards the battery into a black box. I can't find a definitive explanation of this unit. Some people say it's a resonator box that leads to a sensor. There isn't a hole on the underside of the new intake duct, so I hope it is something that just gets left out and closed off. If anyone knows what I'm talking about and what to do about it, let me know. Thanks.

I just scrapped the stock intake on my 95. I think I know what your talking about.
I have no clue what its for but my car didnt blow up when I took it off. My cold did it's job so I'd just go through with the change unless it has a sensor attached on yours. (It didnt on mine)

Any way to post a picture?

Like #11?? That's a resonating chamber to reduce the intake noise. I'm not aware of any sensors on that, so it's only about reducing the sound of the intake. Different years have different size & shape, like # 10 or 12.
http://www.hondaautomotiveparts.com/...13SV40_B01.gif

That is a great diagram, I've been looking for something like that for a long time. Thanks. But what I'm talking about is actually #21. It attaches to the hole on the bottom of the duct and returns to a box not shown on the diagram. Are there labels that go with this illustration?

Where did you find that diagram for that matter?

Here is a photo of exactly what it is I'm talking about.

That looks like another resonating chamber.

www dot hondaautomotiveparts dot com
click the PARTS link.
put in your car's information.
that picture is "air cleaner"

Great site. This is what it is, resonator chamber B, but it does have vacuum lines on it. #8 is a vacuum tank and I don't know where #19 goes. These don't look like critical systems, should I just clamp the hoses? Thanks.

I've never owned a 96...
So that looks pretty strange. Doesn't look like the EVAP canister, but I don't know what it really is.

I plugged the vacuum line leading off of it and just left the sensor in it. It runs fine so I guess it wasn't important. The engine sounds way more aggresive. Thanks for your help.