Preheat oven to 350 degrees F.
Grease a 10-inch tube pan. Combine cake mix, instant pudding, sour cream, eggs, and corn oil and beat together well. In a separate bowl, combine sugar, cinnamon, and pecans. Pour half of batter into prepared pan and sprinkle with sugar mixture, reserving a little to sprinkle on top. Pour the rest of batter into pan and sprinkle with the rest of sugar mixture. Bake 1 hour. Let cool and remove from pan.