What is the purpose of this line
 

When replacing vacuum lines connected to my throttle body I noticed this line connected to my airbox. I haven't noticed vacuum leaks in the hoses around it (Those mentioned in 101 projects for your Porsche), but this line wraps all the way around the engine compartment along the firewall. That makes it difficult to test for vacuum leaks with carb cleaner. I was wondering if anyone knows what its purpose is and whether I should bother replacing it.

http://www.neumonics.com/porsche_images/vacuum_line.jpg

Thanks again for all of your help,
Matt

it comes from the charcoal cannister on the right side of the engine compartment. it's a gas tank vent, and should be connected. there's no intake air leak there. the air flow thru the air cleaner compartment helps to draw in fumes so they can be burned.

on the same note...I found that the canister has 3 places for lines

one thick one and a small one in the back...the picture shows the line that eventually goes to the bigger one in the rear

but I found on on the front as well...where does that line plug too??
mine had no line at all

MJ

I don't believe that there is a line hooked up to the front of the canister. There isn't one on mine and if you look closly at the canister there are no visible marks to indicate that anything was ever attached at that point.

http://forums.pelicanparts.com/uploads/DSC00715ab.jpg

The canister on my car does not have a line connected to that fitting, either.