i've been searching on this all day and i've found nothing, i'm hoping someone can help me out.

i'm putting in my new cold air intake, and i've got an extra hose that i have no idea what to do with. its not the line that runs down the intake to resonater, i plugged that already. the line in question was connected to the stock intake right near the throttle body. it ran over to the other side and connected to some sort of valve on the right side. it has the letters "UP" on it. i have no place to plug it back in on the new intake.

can i just cap it off or is there something else i have to do with it? and what is the valve its running to?

 

The intake should have two pipes. A larger one, and smaller one. Larger goes to valve cover and smaller goes over your intake throttlebody to somewhere on the right side of your motor. I'll look and see where if you need me too. I have an h23 though

 

You seriously found nothing in that? It's really pretty common, but anyhow, that is the starting air valve or 'air boost' valve. It supplies a bit more air on startup, but it doesn't make much difference if it is there or not.

Basically if you want things how there are supposed to be that valve will need filtered air (which is what the stock intake gave it). So use a filter some how, or you can just cap off the valve or remove it...won't make much difference either way.

 

i plugged it with a tee and everything seems fine, but there is one wierd thing. right after start up, when the engine is cold, if i give a little gas and then let off and press the cluth (like backing out of the garage) as soon as is let off the gas it bounces up to 3 grand. but once its warm (like after the drive to work) it doesn't.
is that from that valve being blocked off instead of open to filtered air?