Wall connected on a pair of jump shots as well as two key free throws in the closing seconds as the Wizards broke a two-game losing streak.
He finished with 16 points, as did teammate Martell Webster.
Star rookie Bradley Beal had 14 points before leaving the contest with a sprained ankle while Emeka Okafor donated 12 and 16 rebounds in the victory.
Dorell Wright came off the bench to score 15 points for the 76ers, who fell for the 10th straight time on the road.
2014: The Year in Fashion [PHOTOS]
LeBron James reveals his new Nike shoes