Can someone tell me what this is? It is a hard plastic tube that connects to the underside of the throttle body. I read the haynes manual when I removed my throttle body and it did not mention this.

 

here is a pic from the underside of the throttle body.

 

if i am not mistaken it connects to your emmissions carbon cannister or ac vacuum, i could be wrong though, follow the line and see where it leads

 

The one that connects to the underside of the throttle body is for the EGR...

 

I have to replace all my vacuum lines for the same reason, dry rot and such, everything broke. So I found some drawings of how they were layed out and I also found a post in this forum of what I could use to replace them.
http://chevythunder.com/fuel%20injec...um%20lines.htm
for the layout and
http://store.summitracing.com/defaul...6&N=110&view=2
for the new lines
I hope this helps

 

Thanks everyone for the replys.

88cam your links were very helpful.

I just got a piece of tubing from the auto store and connected the 2 lines together for now.

 

Yeah, EGR tube that mounts by the remote coil.