What's this Hose do?

[Sygerwulf]

Hey guys, I've been reading this forum for a couple months now but I never joined until now because I recently purchased a 91 240sx se so I figured I'd join. Anyway, I have 2 questions that most of you will probably laugh at me for, I know I would. 1) A friend of mine has a 99 GST eclipse that he bought already decked out. He was at the local import shop and someone had opened an AEM cone-style filter out of it's box so they were selling it cheaper then usual so he bought it, however it wouldn't fit on his short cold air intake so he gave it to me. Since I'm having the sr20 swap done shortly I figured what the hell and removed the factory air box and fabricated the cone filter into the air intake where the stock box connected at. What I need to know is what does the vaccum hose that is attached to the air box do? So far nothing has happend with it being dissconnected, the engine runs great, I'm just alittle concerned. Don't wanna leave it just sitting there and no know what it does2) Where is the ATS sensor? Does it connect with a metal clamp or is it just a regular plug in? and where is the thing? I can't find it anywhere.

Thanks for the help guys.

[C-Kwik]

Some people say you can plug it, other people say you can just leave it hanging there. Putting a small breather filter on it is probably the best solution.

Whatever you do, don't plug it. The AIV works off of negative pressure waves in the exhaust and a set of one-way reed valves to draw fres air into the exhaust. Plugging it will not allow the air to be drawn in and the reed valves will just stay open allowing corrosive exhaust gasses to make its way up to the vacuum actuated valve. Eventually the valve will fail. I've plugged 2 S13 AIV systems and both had the exact same failure. It's only a $30 part, but still. Just stick a breather filter on it.

[Sygerwulf]

Thanks guys. I was going to buy a small breather filter on it but I didn't know if I should or not. I'll pick one up tomorrow. And as for the sensor I went back and looked and noticed it lol I guess in my haste I missed. Oh well, thanks for the info guys