Pacioretty added an assist and Brandon Prust also scored for Montreal in the third. For the second straight game, the Canadiens held their opposition below 20 shots on goal.
"You have to learn how to win and this part of that process. We've had two games like this where it's tied 0-0 heading into the third and we find a way to win," said Therrien, the Canadiens' coach.
"We're starting to feel more and more comfortable about playing those tight games. It's a great sign," he added. "It's good for the confidence of the team, of the players. Good teams start to feel comfortable in those games. I don't see any panic. Guys are sticking to the plan."
Cam Ward stopped 23 shots for Carolina, which had its three-game winning streak snapped.
Peter Budaj made 19 saves for his second win of the season and 10th career shutout -- his first in a Canadiens uniform. He made his second consecutive start for Montreal (10-4-1) while No. 1 goalie Carey Price recovers from the flu.
Budaj has allowed only one goal in the two games.
"The guys knew that they had to perform better in front of Peter -- he's always there for them. He always has a good attitude, never complains about anything, and I really liked the way that our team played in the last two games in front of him," Therrien said of his goalie, who gave up nine goals in his first two starts, both losses.
While not often tested, Budaj came through when his team needed it, including some key stops in the late stages of the second as the Hurricanes pressed.
"It's tough but as I said last time, you've got to be ready," Budaj said about facing few shots. "They've got a very good team. They're a hardworking team that has a lot of offensive power, even though they have a few guys hurt."
"We're missing some key guys, yeah, but you're going to have injuries and everyone's going to go through it," Carolina coach Kirk Muller said. "We didn't have that same killer instinct. We didn't have that shooting mentality and we weren't attacking like we normally do. We just didn't have our best game tonight."
The Canadiens had the better opportunities through a fairly uneventful opening 40 minutes, forcing Ward to make big stops on David Desharnais in close and Plekanec on a 2-on-1 with P.K. Subban coming out of the penalty box.
Prust finally broke the scoreless deadlock 2:06 into the third period. Lars Eller led the rush through the neutral zone before dishing off to Alex Galchenyuk. The Canadiens' rookie evaded Hurricanes defenseman Bobby Sanguinetti with some slick moves before finding Prust driving to the net.
"When he's going and dangling like that, sometimes you've got to make sure you don't just stop and watch," Prust said of his 19-year-old linemate. "I've learned to keep my stick on the ice when he's got the puck because he'll find you, sometimes when you don't think he's going to get it to you."
The Canadiens doubled their lead when Plekanec took a pass from Pacioretty and tossed a shot from inside the left circle at 12:03. The puck bounced on to Ward's back and into the net, giving the Canadiens' center his eighth goal of the year.
Pacioretty finally scored his first of the season at 12:21 when his innocent-looking shot from the red line trickled past Ward.
"That's what we talked about in the intermission -- we wanted to get off to a good start and start putting the pressure on them right away," Prust said. "They kind of took it to us a little bit at the end of the second, so we wanted to come out and change that momentum."
Price dressed as Budaj's backup after missing Saturday's game with the stomach flu. ... The Canadiens were without rookie wing Brendan Gallagher (concussion), while Yannick Weber and Tomas Kaberle were healthy scratches. ... Gallagher's absence put forward Ryan White back into the lineup for the first time since Feb. 7 in Buffalo.
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MONTREAL, CANADA - FEBRUARY 18: Max Pacioretty #67 of the Montreal Canadiens shares a laugh during warm-ups prior...