It was the third win in four games for the Mavericks, who allowed all of a 15-point, fourth-quarter lead to disappear.
Detroit took a 97-96 advantage with 2:29 to play on a 3-pointer by Khris Middleton, but Nowitzki then made his back-to-back baskets to put the Mavericks back in front.
Two free throws by Darren Collision gave Dallas a three-point lead with 3.8 seconds and the Mavericks survived when Charlie Villanueva misfired on a 3-point attempt at the buzzer.
Detroit was led by 21 points from Brandon Knight in what was the Pistons' seventh loss in eight games.
Members of Congress to keep receiving porn magazine
Rosie O'Donnell unveils nearly 50-pound weight loss