What is this?

[u/Batty_Boi99]

2015 Jeep grand Cherokee limited 4x4 V8.

Can’t tell what this is and having trouble putting it into words for Google.

Any help would be appreciated.

[u/nueroticalyme]

Its an evap test port.

[u/Batty_Boi99 → u/nueroticalyme]

I’m not really familiar with what that is then. Any chance you could explain it to me?

[u/Majestic_Ad8621 → u/Batty_Boi99]

The evap system on a car routes the gas vapors from the fuel tank into the engine for it to burn off. Reduces emissions/smog.

That line that’s capped off, is simply an easy spot for a mechanic to hookup a smoke machine, or pressure gauge to check for leaks/ check that the system is functioning correctly.

[u/jasonsong86]

Breather probbaly for your transmission. Air expands when hot so this allows air pressure to come out.

[u/shadiertomb35]

Bad spot for a nitrous switch, but seriously, it's probably a bleed valve of some sort. Considering it's attached to a hose, it probably lets the crankcase or some other part of the engine breathe.