help ID this hose

Hello ! I was working on replacing my starter in my 2002 C4 cab and found this hose dangling all of a sudden..anyone kind enough to ID what hose this is and where it goes ? This is after I've removed the air box, throttle body etc. It's right above my alternator but I've no clue what it is. Hose above alternator

That looks like the one that goes to the rear part of the manifold. little throttle body looking thing in the rear tube between the manifolds

Should go into the back of the rear crossover tube to work the valve. U may beable to get your hands back there but i think u r pulling the rear crossover. U can slide the couplers over but its difficult because they have internal stops that the front couplers do not have.

Thanks ! Any idea what it does and where to connect it ? Has it been cut ?

Quotes source post: 16799451

aa... Thank you. I'm still new to learning about the engine in itself. Any thing you recommend for me to go through to figure out how to put this back ? Also, is it ok for me drive with this out ? What am I actually looking at in that case ?

The buterfly valve actuates at certain rpms. Its for effiency so its ok that its not working, some have removed all together. The grey block that it comes from is a changeover valve. It opens so it pulls a vacuum so i would cap the end if u r not gonna fix it. U r almo​​st there do why not fix it?

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Thank you so much. I was able to find the rear crossover tube, loosen the hose clamps , rotate it and plug it back in. It did go in with a click - so I think it should be good.

Here is what that thing does:

Brilliant. I had no idea about the oscillations on the intake air column. Resonance supercharging. what a brilliant idea ! Thanks for sharing. If I may - What publication/manual(?) is this from ?

I'm in the process of replacing my oil filler tube, and I started working on removing the alternator, and noticed that same skinny little hose was broken in two pieces, about 1.5" from the end of the formed-rubber "U" hose. The longer piece was just laying there, but when I touched it, I could see the rest of it moving behind the engine. I had the front crossover/plenum removed, so I reached in there and when I touched the hose, it fell into my hand. Getting the replacement hose should be the easy part. Reconnecting it is the issue. Any guidance on how to get it reconnected at the rear of the engine would be appreciated. I started trying to take the other crossover out, but it doesn't look as simple as the one connected to the throttle body. Thanks! Mike

Sold by the meter. 3 meters will do the whle car. 00004320501 90* hose 92857471705

You might have to lower the engine to reach over the top or just pull the throttle body off and see if you can reach the rear plenum tube.

Quotes source post: 18105999

I lowered the engine a little, and had already removed the throttle body and front plenum. I loosened the clamps on the rear plenum and was able to rotate it a little. When I rotated it toward the front of the vehicle, a loose rubber hose appeared at the back (see arrow in pic). It's attached to the crossover plenum because when I rotate it back, the hose disappears. It doesn't have anything plugged into the end that was dangling down. I'm guessing this is where the other end of the hard vacuum tube goes. Can someone please verify this is correct? Thanks! Mike Rubber hose that appears when I rotate the rear crossover plenum.

Yep, that's where it goes..

Quotes source post: 18106548

Thanks!