Phaneuf was playing in his hometown for the first time since he was acquired from the Calgary Flames last season.
The Toronto captain makes his return to Calgary's Scotiabank Saddledome on Thursday, where he will likely receive a frosty reception.
"It was a big win for our team," Phaneuf said. "We knew this was a big trip and we talked about starting it on the right foot. We played a really solid game. We didn't give up a lot and we capitalized on our opportunities. The only negative part of our game was how much we gave up in the first, but we responded well."
Kris Versteeg had a goal and an assist for Toronto while Mikhail Grabovski and Phil Kessel also scored for the Leafs, who have won two in a row and four of their past six. Toronto moved into a three-way tie for 10th in the Eastern Conference with Buffalo and Carolina.
Maple Leafs coach Ron Wilson said the key to the win was how the team bounced back from a competitive first period.
"We were trading chances with them in the first period, but we felt if we played better defensively and didn't turn over as many pucks at the offensive blue line that we would be able to get a lot of scoring opportunities and we did," he said. "And at the same time draw some penalties which we did. I thought in the second and third period we played as well as we have in a long time."
Jordan Eberle scored for the Oilers, who have lost two in a row and three of four to remain in last place in the West.
"We started to take too many penalties and it disrupted the flow of the game," Eberle said. "We just couldn't get the momentum back. When you don't come out ready for the second period that's when you take penalties."
Oilers coach Tom Renney said his team's power play was just as much to blame as penalty killing.
"We took ourselves out of it in the second period with bad penalties and a power play that looked like a minor hockey power play. And maybe not that," he said.
The Oilers came out strong, but it was the Maple Leafs who struck first about six minutes in as Phaneuf beat Oilers starter Nikolai Khabibulin with a shot from the point.
Edmonton tied it six minutes later as Ryan Whitney did a good job keeping the puck in at the point and sent it to Sam Gagner who slid a pass under Leafs defenseman Francois Beauchemin to Eberle to give the rookie forward his seventh goal of the season.
Toronto had a good chance to regain the lead with under a minute left as Versteeg had an open net to shoot at in a scramble, but Khabibulin dove across to make a pad save.
The shots were 12-12 after the opening period, significant for the Oilers in that it tied their shot total from the entire game in Sunday's 2-1 loss to Vancouver.
The Leafs went up 2-1 at 8:28 of the second on the power play as Clarke MacArthur faked a shot and instead sent a nice feed to Grabovski, who got his ninth goal.
Toronto made it 3-1 with two minutes to play in the second as a Versteeg shot dropped into the crease behind Khabibulin and went in off the skate of defender Jason Strudwick as the Oilers attempted to clear it.
Phaneuf didn't make himself any more fans in his hometown in the third as he wrapped an arm around Oilers rookie Taylor Hall long after a whistle, prompting Dustin Penner to jump him and earning the Toronto captain an unsportsmanlike call.
But it was Toronto that would score on a power play a couple of minutes later as Versteeg made a nice pass through the crease to Kessel, who got his 12th goal.
The teams split the season series. Edmonton took the opener 5-0 in Toronto on Dec. 2. ... Defenseman Jim Vandermeer, out with a sprained ankle, joined the Oilers' injured list which includes forwards Ales Hemsky and Shawn Horcoff. His spot on the blue line was taken by veteran Jason Strudwick, who had sat out the previous 13 games. ... Out for Toronto were forward Mike Brown (broken finger), forward Jay Rosehill (day to day with a broken nose) and defenseman Mike Komisarek (out 1-2 weeks with a finger injury).
Copyright by STATS LLC and The Associated Press
Arena: Rexall Place Location: Edmonton, Alberta
Referees: Eric Furlatt, Francis Charron Linesmen: Darren Gibbs, Anthony Sericolo
Attendance: 16,839 (100.0% full)
Team Stat Comparison
Power Play Goals
Power Play Opportunities
Shots on Goal
Dion Phaneuf (1)
Assists: Phil Kessel, Colby Armstrong
Jordan Eberle (7)
Assists: Sam Gagner, Ryan Whitney