I just got a '83 Buick Regal (I know, I'm a pimp) with 40,000 original miles, it runs fine some of the time, but for the most part it smokes black, hesitates while driving, stalls when comming to a stop, and smells like raw gas. My thoughts was the 02 sensor, but I figured I'd ask what you fine people thought.

 

black smoke means it's running too rich. My thoughts are o2 sensor too, good place to start anyway.

 

If it has a cat on it, it's probably smoked too.

 

Carb or Fuel Injected?

 

sounds like either a rich condition or a missfire, your egr could be stickin open