Hose identification- what goes here?

Hey, this has been a bit of a project and it’s getting put back together. I cannot figure out what hose goes in this spot (see pic) and could use some help. Connects under the fuel pressure regulator. Any diagrams or sites to look them up on are greatly appreciated. Thanks!

 

It might also help if I let you know it’s a 2003 3.4L

 

I just looked at the pics I took during my VC job and I couldn't tell for sure. Maybe it's a line coming off your charcoal canister..?

See the hose I have wrapped in tape and marked 2? Follow that in your engine bay and look for a loose hose not attached to anything.

 

@NurseJenny
That is the driver side branch of the "air assist" plumbing. The entire hose route is shown below, disregard the red and blue arrows.
Yellow arrow is the start at the Idle Air Control valve mounted to the underside of the throttle body, it carries air. It is the lowest rear pointing fitting. There are three hoses in that location, note that two are coolant. One of the coolant lines can be seen below, the hose above the yellow arrow. Note that it connects to the intake manifold "just forward" of the pass side branch of the air assist line. The other coolant line on the IAC points forward. The hose for this connection (not shown) does a quick U turn and heads to the rear. These are all "molded" hoses and should be fairly easy to identify.
The "air assist" line connects to a black "Y" connector that splits the air flow to a fitting on each side of the intake. In this pic the FPR is concealing your mystery connection.

 

^ This is correct.

 

@Dirty Pool
Thanks for the info and the pic. I will check that when I get home from work. The pictures I took when I tore it apart didn’t give me the close up I needed.

 

Here are a couple of other previous posts which highlight the line in question:
https://www.tacomaworld.com/threads...-can-i-do-anything-else.742997/#post-26452420

And another showing the vacuum line in place:
https://www.tacomaworld.com/threads/another-p0171-thread.739338/#post-26331803

 

Another angle/ discrip @ 18:18

Toyota 3.4 Liter 5VZ-FE Engine Replacement (Part 3 - New Engine Build-Up) - YouTube