Lanier Brown crashed his corvette into another vehicle on the northbound Grand Concourse at Bedford Park Boulevard just after 10:30 last night.
Investigators said Brown fled the scene, but he was later caught.
Two people in the other car, a man and a woman, were treated for neck and back injuries. They are in St. Barnabas Hospital in stable condition.
Brown has been a firefighter for the past three years. He works in Manhattan.
He was suspended 30 days without pay, which is the maximum allowable suspension.