2005 Audi A4 1.8T B6 EVAP Line Question

[5-Valve-Sam]

Good Day -

I am quite new here, but have taken advantage of countless tips and tricks and DYIs thru the years I have owned my Audi.

For reference, it is a 2005 A4 B6 with a 1.8T and a 6 spd standard transmission. Has been an excellent vehicle for the past 105k miles (bought with 104k, and now has 209k).

To make a long story short, I just performed a full top end overhaul (valves/guides/etc) along with doing a timing belt/all other belt-line parts swap (2nd time during ownership for me).

I decided to follow the DIY in this link: https://www.audizine.com/forum/showt...simplification

For those who did not click on it, it is a full removal of emissions lines, and is very comprehensive. The only question I have after following it step-by-step is as follows:

What is the line that comes off of the firewall at about 8 o'clock that previously connected to the EVAP lines? I have included a picture from my vehicle posted below (line circled in blue):



After I get an answer on what the line is, what is the best way to handle it (cap it, leave it open, attach it to some other system)?

Thanks again for all of the help on this, and feel free to guide me to a link that I was unable to find.

[Furly]

the fuel evap line comes from your fuel filter area, and runs all the way to the front passenger side fender and then up through the side of the fender into the engine bay and then goes across the top by the firewall. i switched to return fueling and completely removed and capped off the evap system. you can pull a diagram online and redo yours if you are keeping it returnless. its a very simple and straight forward system.