Identifying intake vacuum? s14 SR

[2plus4plus0eq6]

I just noticed this. I capped my hole off because I didn't think it was necessary (the line coming from the intake pipe to the head). I know there are 2 smaller holes beside this large one.

Can anyone tell me why air needs to be directed to this? and what would happen if it wasn't connected?

Thanks

http://i84.photobucket.com/albums/k10/dylanw83/sr20det_vacuum.jpg

[benefitx]

well that would be your coolant inlet...

[2plus4plus0eq6]

Thanks, but I meant the line just above and to the left of that coming off of the intake pipe (I should have drawn my arrow longer). Its some sort of vacuum or something. I'd like to know if its necessary and what exactly it does.

[sean350z]

It's for the IACV and it's important with it capped I don't think you're idle would be very smooth.

[fliprayzin240sx]

The black rubber hose coming of the cold pipe into somewhere under the manifold just between the manifold and block right? If it is, like stated above its the Idle Air Control Valve. If you cap it, your car will die everytime the throttlebody is closed since air wont be getting into your engine.

[Slidin240Wayz]

It runs from the coldpipe just like it is in the picture.

Carlos

[2plus4plus0eq6]

wow thanks a lot guys. that explains a lot, how about the 2 smaller lines right beside that iacv on the black?

[Slidin240Wayz]

I don't think there are lines on the iavc, only plugs.

[sean350z]

There is one medium nipple on the back of the intake manifold that is for the brake booster, 2-3 small nipples under the throttle body for BOV, charcoal canister, etc, which is what I think you are talking about.

[2plus4plus0eq6]

Yup, you're right. I took a look and the small nipples are the ones coming off of the throttle body.

I took my canister out and I don't have a BOV at the moment, but when I do, could I possibly hook it up to any other vacuum line? which means I can just cap off all of the nipples on the throttle body?

The only one that is really necessary is that Idle control air valve Im assuming

[fliprayzin240sx]

Yes those nipples are what you tap off for anything vacuum related. BOV, gauges, etc etc.

[2plus4plus0eq6]

perfect. ok thanks for the help guys