1984 Chevy Monte Carlo poor running

My name is Scott I recently purchased a 1984 monte carlo with a 3.8 v6. I purchased this vehicle because of the low mileage, and how clean the vehicle was. Here in michigan the rust eats the cars alive! So I purchased this vehicle the old owner said that had sat for over a year since was started last, after jumping the battery the car started, it didnt want to run. It would die, so I had to sit there and feather the gas pedal, eventually after about 2 minutes of working the gas the car would idle. When I went to drive the car home, I noticed when you get the car at about 2000-2500 rpms it would loose power and bogg down like it is being robbed of air? So I removed the air cleaner, I noticed a vacuum line that was disconnected, when I put my finger over the hose the idle would slow down, but still idles high? I do not know alot about carburated cars, any help would greatly be appreciated. Scott