Metal Tube

I have a 1995 Lumina which I have obtained from a relative. The previous owner had trouble with the car stalling and it gave them troubles with starting, occasionally.

I've had the fuel injector replaced and bought a new battery. I took it to the mechanic again because the battery seemed shifty (the lights would frequently dim, etc). He said that the alternator was fine. A few days later, the brand new battery died. I purchased a new battery, and yesterday morning, I went to start it and it clicked over and I could hear the starting clicking over and the solenoid humming, but the car didn't start. I jumped it and then it started.

After looking in the engine, I noticed that a thin metal pipe that leads up to the manifold was disconnected. I reconnected it and it's been starting fine thusfar.

Is it just starting fine because it's been recently jumped, or could whatever that metal pipe is have fixed it?

I apologize for not using a specific name, but I couldn't find it anywhere. Not even in my Haynes manual.

Any photos? This is a generic 1996 Lumina - Can you point out the mysterious pipe?

http://mysite.verizon.net/strey/files/W-BodyEngineView.jpg

Though it isn't visible in the image, it's under the area I've highlighted below.

http://img383.imageshack.us/img383/7649/labeledkh1.png