Carter beat former teammate Jonathan Bernier with a wrist shot between the legs on a two-on-one at 9:40 for his eighth of the year. Defenceman Paul Ranger failed to keep the puck in the Los Angeles end, creating the odd-man rush.
Martin Jones, a 23-year-old rookie from North Vancouver, earned his fourth straight win in four career NHL starts for Los Angeles with ex-Leaf Ben Scrivens on the bench. Kings No. 1 Jonathan Quick is out injured.
Jones came into the game with .973 save percentage and 0.65 goals-against average. He had stopped 73 of 75 shots and hadn't been beaten in 142 minutes 46 seconds.
Cody Franson scored for Toronto (16-13-3), which deserved better on the night.
The Leafs were without captain and top defenceman Dion Phaneuf, serving the first half of a two-game suspension for a weekend hit on Boston's Kevan Miller. But winger Joffrey Lupul returned after a seven-game absence due to a groin tear.
The Leafs showed more jump than a Los Angeles team playing for the second night in a row but were unable to convert their advantage into goals.
Still, the Kings came in riding a season-high four-game winning streak, hot on the heels of a 6-0 win in Montreal, and were 11-1-4 in their last 16 games.
The Leafs, meanwhile, had just two regulation wins in their last 17 starts (a stretch during which they went 6-8-3).
Los Angeles had outshot their opponents in 21 of their previous 31 games. In contrast, the Leafs had been outshot in 27 of their 31 previous games.
But on this night, Toronto outshot L.A. 11-8 after the first period, 21-16 after the second and 38-23 at the end.
But Los Angeles scored first on the power play at 10:30 of the first period, on a high wrist shot by Doughty from the top of the circle. It was his sixth goal of the season and the 200th point of his 396-game career. Peter Holland was in the box for holding as the Leafs' penalty kill, which came into the game ranked 26th in the league, continued to wobble.
Jones stopped Nikolai Kulemin from point-blank range twice later in the period.
The Leafs outplayed the Kings in the first period but trailed 1-0 as the visitors extended their record of not allowing a first-period goal in 17 straight games.
That made for some Twitter banter. "Thoughts on the first period?" asked the Leafs' official Twitter account.
"It was pretty pretty pretty good," replied the Kings, via their official account.
The Kings' record when scoring first improved to 15-2-2.
Jones stopped Phil Kessel all alone after the Leafs sniper stole a pass and broke through the defence early in the second. It took the Kings 5.5 minutes to get a shot on net in the period.
The Leafs had their chances but either misfired or were denied by the steady Jones.
That changed when Toronto took advantage of a 64-second 5-on-3 chance after Doughty joined Willie Mitchell in the box with 5:57 remaining in the period.
Franson scored 27 seconds later, snapping a shot from a poor angle at 14:30 on a slick cross-ice pass from Kessel, with Jones unable to slide from one side of the net to another in time. It was Franson's first of the season.
But Jones prevented further damage by stopping Lupul from in close with the second penalty about to expire. Doughty scored seconds later when he jumped out of the box but the play had been whistled dead for an altercation between Lupul and Slava Voynov at the other end of the ice.
Bernier heard the whistle and did not attempt to make the save.
The Leaf goalie saved Lupul's blushes early in the third when he stopped a Justin Williams' backhand after a Lupul giveaway in front of net.
Jones made several big saves as the clock wound down to preserve the lead.
Rookie defenceman Morgan Rielly returned to the Leafs lineup after being a healthy scratch the last three games. Jean-Michael Liles sat out the game.
NOTES — The Kings' last game at the Air Canada Centre was Dec. 19, 2011, when Los Angeles won 3-2 in a shootout. It was the last game before Darryl Sutter took over as coach.