What is this t-fitting coming of the intake manifold runner?

Hey guys its my first time posting to the forum but I have been browsing / reading up on LGT info since February when I purchased my car .

 

Anyway I have finally gotten to the point at which I am able to get the car tuned by Infamous1. I got the car through a 3rd party (got online, car was wrecked) so I have no way of knowing what the previous owner had done to the car besides the obvious....which was a lot. I came across some interesting "handy work" last week when I was inspecting my intercooler and vacuum lines in preparation for making a couple pulls tomorrow at a local drag strip test and tune.

 

There is a vacuum line running from the fuel system to the intake manifold runner with a T-fitting in it. I looked at my friends 2011 WRX and he doesn't have this. I'm thinking this might have been something to monitor boost or adjust boost with relation to fuel pressure that the previous owner rigged up but yanked when the car got taken to auction?

 

I've attached pics of the culprit.

 

 

Thanks!

-Mike

That t is not usually there but I'm going to say that the previous owner used it as a tap for a boost gauge. That is all. I have an 08 GT.

you wouldn't use that to adjust boost. It looks like the end that goes to the fuel pressure regulator. The car uses vacuum lines from the manifold to the FPR since it increases fuel pressure in a 1:1 relation.

Would its be ok to leave it, even in its ghetto rigged state? I have some vacuum line that I could run directly from the FPR to the manifold runner nipple but it is going to be hard to get my hands on the FPR end. Seems removing just the one screw holding the bracket (picture 1, center-left) doesn't gain you much wiggle room on those hard fuel lines. I'll search the forums and try to find a procedure to remove the bracket / fuel lines more completely but until then I'm going to assume that the "plug" will hold.

You can leave it. Just make sure there are no leaks in that fitting. You can replace the affected vac line like you mentioned, that's what I'd do.

Been searching for some info on removing or getting the driver side of the fuel system in a more accessible location and I'm coming up empty. Basically all I want to do is get the driver side and FPR some wiggle rooms so I can actually get to the nipple on the FPR and intake manifold runner. I learned by removing the single bolt that attaches the FPR bracket to the manifold that there are more things that need to be loosened or disconnected. Any guidance would be appreciated since I believe my new tunes higher boost is slowly pushing my zip-tied screw "plug" out of the end of the line. I just hope I don't a big pop from the screw popping out the end of the tube under WOT...no boost going to FPR, engine super lean, bye bye engine.....

 

-Mike