Goalkeeper Bill Hamid blocked Sacha Kljestan's free kick, but the ball squirted away and Sam beat his defender to the loose ball for the equalizer.
Last week, D.C. United (3-1-1) became the fifth team in MLS history to win consecutive games with a stoppage-time goal.
Perry Kitchen gave United a 1-0 lead after heading Taylor Kemp's 26th-minute corner kick off the post and into the net. In the 67th minute, Chris Rolfe navigated through New York's defense and found Kitchen, who took one touch and drilled a shot for a 2-0 lead.
New York (2-0-2) answered a minute later when Damien Perrinelle headed in Felipe's corner kick for his first MLS goal.
Luis Silva's free kick in the 76th minute was headed away at the goal line by New York midfielder Dax McCarty.