2001 Chevy Impala NEW CAR

I JUST RECENTLY PURCHASED A IMPALA AND ALREADY IM HAVING PROBLEMS. WHEN I TAKE OFF THE CAR JERKS AND EVERY TIME I GIVE IT GAS I JERKS MY UNCLE SAYS ITS THE CAD CONVERTOR BUT I HAD ONE OF THOSE GO WRONG BEFORE AND IT DID NOT CAUSE THAT I THINK ITS THE TRANNY BUT REALLY HOPE IT ISN'T WHAT DO YOU THINK OH YEAH AND THERE LIKE A BURNING SMELL TOO GO FIGURE...