It was the second victory in as many days for the surging Flyers against their cross-state rivals.
Philadelphia had a power-play goal, a short-handed goal and was a perfect 5-for-5 on the penalty kill in a 4-0 win against the Penguins at home on Saturday.
"The power play was good again, the penalty kill was good again," Flyers coach Craig Berube said. "Lots of shots, lots of chances. We played a pretty solid game."
Philadelphia improved to 5-1-1 in its past seven. Including playoffs, the Flyers are 10-2-1 all-time at Consol Energy Center (8-1-1 in the regular season).
"I know the boys in this locker room love playing against them," said Philadelphia goalie Steve Mason, who allowed three goals on 48 shots during the weekend sweep.
"Whether we're in their head or not, we don't really care. We get amped up to play against them."
Defensemen Brooks Orpik and Matt Niskanen and recent call-up Jayson Megna scored for the injury-riddled Penguins, who lost two straight in regulation for the first time since dropping three in a row from Nov. 6-13.
"(The post) is all I gave him, though," Mason deadpanned. "It's part of the equipment."
Pittsburgh still holds a commanding lead in the Metropolitan Division, but remained three points behind the Boston Bruins in the race for the Eastern Conference's top seed.
The Penguins fell to 18-2 in March home games over the past three seasons. They were 10-0 at home last March.
"The last two seasons, March has been too easy for us," Niskanen said. "We go through with just a breeze, and I think we go into the playoffs overconfident. Right now, we're in a little bit of a bump in the road and we're going to have to fight for it."
Simmonds assisted on Brayden Schenn's goal 2:06 into the game and then scored twice in a 6:54 span to give the Flyers a three-goal lead 14 minutes in.
Read's goal was his third goal of the weekend for Philadelphia, which entered Sunday holding down the eighth and final spot in the conference standings.
Making starts on consecutive days for only the second time this season, Marc-Andre Fleury made a lunging glove save on the first shot he faced Sunday, from Simmonds.
But he couldn't control the puck in his glove and it fluttered to Schenn in the slot, who slid it in past a diving Penguins defenseman Robert Bortuzzo for his 17th of the season.
Claude Giroux assisted on Simmonds' 20th and 21st goals, the first of which was with 13:13 left in the first when he deflected a Kimmo Timonen shot from the point. Simmonds made it 3-0 when he corralled a rebound while uncovered and beat Fleury to end his afternoon after just 13:41.
"The way we started the game," Timonen said, "it was perfect."
Under siege by a Philadelphia attack that Pittsburgh had issues dealing with, Fleury allowed seven goals on 55 shots in less than four periods covering 24 hours against the Flyers.
Rookie Jeff Zatkoff replaced him.
Without their top two goal-scoring wingers -- Chris Kunitz (lower body) and James Neal (concussion) -- for the second consecutive game, the Penguins were held to fewer than four goals for the eighth consecutive game. That hadn't happened to them since early in the 2011-12 season.
A pair of defensemen pulled Pittsburgh within a goal with slap shots from the point that found their way through traffic and past Mason.
Orpik was credited with his second of the season with 2:27 left in the first, and Niskanen tallied his 10th at 5:50 of the second.
But Read had a short-handed goal for the second straight day, finishing a 2-on-1 break himself with a wrist shot for his 19th of the season.
Megna tapped in a nice pass from Brian Gibbons to cut the Penguins' deficit to 4-3 with 3:41 left in the second, but Pittsburgh failed to score on 11 third-period shots.
Pittsburgh has the NHL's No. 1 power play and No. 2 penalty kill but lost the special teams battle 5-0 over the weekend against the Flyers.
"We play Pittsburgh a ton of games a year, and our power play has been successful against them since I've been there," Simmonds said. "I think we kind of know where they're going to come from.
"I don't want to say we try to pick them apart, but we know where they're going to come from and we try to change our point of attack. And it seems to be working."
The Penguins announced after the game that D Kris Letang was cleared to practice and will practice with the team Monday. Letang has not played since suffering a stroke Jan. 29. ... Penguins F Beau Bennett was cleared for full practice after missing the past 43 games with a wrist/hand injury. ... Penguins D Simon Despres was a healthy scratch. ... Giroux has five assists in the past three games. ... Crosby, who had 74 points over his first 45 career games against Philadelphia, was scoreless in the home-and-home series.