Hardlines running along passenger frame rail

[GripSpec]

I started a winter tear down on my s13, and found a bend in one of the metal hardlines on inner passenger frame rail. Tracing it up towards the firewall, I find that the hardline leads to rubber line that leads to.... nothing?

Are these fuel lines? If so, is this line not used in after swapping to an SR (hard to imagine that could be the case)? I always thought they were brake lines, but never thought much about it (other than checking for rust). I swapped and SR into this car 5+ years ago and it has been through multiple auto-x seasons since then. I had a friend helping with the swap at the time so I'm thinking that is when this line might have been removed/disconnected.

Here is a stock photo of the lines (four lines next to frame rail). The line in question is the inner most line closest to trans.
https://c4.staticflickr.com/6/5672/31170611451_6bee1c7737_z.jpg

Here is a shot of my lines from the top in the engine bay (between passenger side strut tower and intake manifold)

https://c2.staticflickr.com/6/5513/31170611921_636fe0d9cf_z.jpg

[zombiewolf513]

For future reference, there's an 'identify this' thread:
http://zilvia.net/f/showthread.php?t=174916

Pretty sure that cut line is for the vent or egr system's charcoal canister. Been a minute.

[KAT-PWR]

Fuel tank vent

[GripSpec]

Apologies for not using the thread mentioned above. Thanks for the replies.

Are all 4 lines fuel related, or are they a mix of fuel/brakes?


Sent from my iPhone using Tapatalk Pro

[derass]

Those 4 lines are: Fuel Supply, Fuel Return, Rear Brake Circuit and EVAP.

As mentioned above, the disconnected line on your car is EVAP. Can't remember exactly how it makes it's way over there, but I do remember that it eventally runs along the top of the driver's side frame rail where it's finally connected to the Charcoal Canister, which is attached to the radiator support, also on the driver's side.

Here's the best pic I could find. This is an S14 but S13 is identical. The line connected to the top of the canister is the one of the four that runs under the car to the fuel tank.

http://speed.academy/wp-content/uploads/2014/05/nissan-SR20DET-swap-105.jpg

[MR_GUTTI]

Fuel to filter, fuel return to tank, tank vent and rear brake.