Montreal picked up its first point in three games since ending its team-record five-game winning streak. Sporting KC, which leads the East with 56 points, is 8-4-3 on the road this season.
"This was a massive point for us, for sure," Kansas City coach Peter Vermes said. "A huge opportunity for us to not necessarily separate ourselves immensely, but every one of those points adds up at the end of the season."
The Impact claimed their 40th point with the draw, which kept them unbeaten in their last seven at home. Montreal, which is seventh in the Eastern Conference, had won its six previous home games since a 3-1 loss to Sporting KC on July 4.
"At the end of the day, until somebody tells me that we're mathematically out of it, we're still in it," Impact captain Davy Arnaud said. "The only thing we can now go do is win our next three games and hope that it's enough. We know it's going to be difficult because teams already have close to the points that we can possibly get, but until we're out of it we're going to keep on pushing."
Montreal goalkeeper Troy Perkins made a point-blank stop on Kei Kamara 14 minutes into the game. Justin Mapp had the Impact's best opportunity in the first half, but his shot went wide of the left post.
Sporting KC midfielder Jacob Peterson was on the bench after coming out of the game when he was shown a red card by referee Jorge Gonzalez in the 90th minute.
Arnaud and Impact midfielder Collen Warner were shown yellow cards. Warner will miss Montreal's next game in Houston on Oct. 6.
The Impact have three games left in their season with two on the road. Kansas City is undefeated since July 28, with a 5-0-3 streak since a 2-1 home loss to Columbus.