LS4 Performance - What am I missing?




View Full Version : What am I missing?


JWMayes
07-26-2011, 09:20 AM
Hey guys, I tried searching for a topic like this, as I thought I remembered seeing something about the same thing a while ago. But I couldn't find anything. I am in the process of being LewTuned, and my LTFT's are way off, so I have been searching for a vacuum leak somewhere, and the other day I came across what looks to be a vacuum line fitting missing the hose. Does anyone have any idea of what goes here, if anything at all? The fitting is on the neck of the intake, between the throttle body and the rest of the intake, in the pic it is just above the brake booster line (says ls4). Thanks for the help, it is appreciated.


smokin06impala ss
07-26-2011, 10:22 AM
Nothing goes there ,just plug it up I bet that is your vacuum leak.

Bryan921SS
07-27-2011, 11:55 AM
I checked my 07 and there isn't anything on that fitting.

Do you think it is something important?


1CL3ANSUP3RSPORT
07-27-2011, 12:34 PM
When I put my trans in I came across that,and thought I was missing something but nothing goes there and there no hole for vacuum line.Hope that helps...

LS1 Racing
07-27-2011, 12:41 PM
Haven't a clue, but if you look in that picture, you'll see the vacuum line coming out of the valve cover that goes to the intake elbow. On my car, that was leaking at both ends. I pulled that whole cap thingy off and replaced it with a vacuum hose and zip-tied it at both ends. My LTFTs went from 10-11ish down to the 6-8 range.

06silverss
07-27-2011, 12:46 PM
It should be plugged unless you have a ported intake manifold. I had a vacuum leak when I installed mine and bingo that was it. Stick your finger over the end of it with the car running and you will definitely know if its coming from there.