Ok, I have a 94 a4 Z28 and the air intake is stock (except for 1le elbow). I recently did the TB bypass, yesterday actually, and when I got finished, I started my car and it was idleing really bad. I got out and checked to make sure everything was plugged in and hooked up correctly, and it was. I started it again and the idle was really rough and choppy. Then I remembered when i began taking all of the air intake stuff off before doing the TB mod, the rubber hose to the right of the MAF that connects to the plastic part of the intake wasn't connected. So when i got out, I pulled it (the hose) off of the plastic piece, and the idle suddenly improved, like normal. What's this hose for and why would it be idling rough when it's connected? I appreciate any opinions!! Thanks guys!

 

If I'm not clear enough or you have any ???'s just let me know.
Thank's again!