Pedersen had a hand in goals for David Dunn and Ryan Nelsen which sandwiched a fine strike by Brett Emerton and consigned Rovers' 7-1 embarrassment at Manchester United to distant memory.
The Norwegian was too much for Wolves to cope with and McCarthy must now try to lift a team who sunk below West Ham on goal difference after Nelsen hit Rovers' third.
McCarthy's men had started superbly with Matt Jarvis bringing a first-minute save out of Paul Robinson and both Stephen Ward and Ronald Zubar rattling the woodwork.
Jarvis cut inside the flat-footed Michel Salgado and hit a rising shot which was parried well by Robinson, who found himself back in action with less than five minutes on the clock.
Robinson tipped Stephen Ward's low drive against the post and after Rovers failed to clear Zubar scooped in an effort which hit both the crossbar and the post before rebounding to safety.
But in a surprisingly high-octane start Rovers also fashioned a good chance when El Hadji Diouf wriggled his way to the by-line and sent in a cross which was tipped off the head of Pedersen.
The visitors failed to build on their early momentum and were made to pay in the 29th minute when Pedersen's long corner was flicked back by Nelsen and met by Dunn in the six-yard box.
Dunn's firm header was frantically booted clear by Kevin Doyle but referee Howard Webb had no hesitation in deeming the ball had crossed the line - a decision TV replays proved correct.
Wolves seemed unfazed and came close two minutes later when Robinson could only parry a fine long-range drive by midfielder Nenad Milijas.
Christophe Berra flicked another dangerous Pedersen set-piece inches past his own post but the visitors continued to show promise on the break with Jarvis and Doyle constantly probing.
But Rovers extended their lead in the 42nd minute when Roberts raced onto a long ball by Salgado and flicked the ball cleverly into the path of Emerton, who swept home a fine left foot shot.
Wolves forced a pair of early second-half corners which came to nothing then substitute Stephen Hunt's run into the box was intercepted by Gael Givet.
But yet again it was a Pedersen free-kick which teed up Rovers' third, his left foot set-piece curling around the Wolves wall and finding Nelsen who prodded home.
Confidence seemed to be draining from the visitors with Jarvis electing to cross rather than go for goal himself after picking up a long cross-field punt from Kevin Foley.
And Rovers looked more likely to extend their advantage with Roberts thwarted in his bid to race clear in the 63rd minute by a marginal offside decision.
Pedersen's set-piece magic temporarily deserted him when he fired a free-kick high over the crossbar in the 68th minute, then Phil Jones beat two defenders but failed to get his shot off in the box.
George Elokobi came close to reducing the deficit for Wolves in the 71st minute when he was fed by Jarvis and fired a rising left foot shot which Robinson did well to parry.
Wolves came close again on 77 minutes when Hunt met a Jarvis cross with a powerful low drive which was kept out by a superb one-handed save by Robinson.
And Hunt was denied again deep into injury time when his twisting shot from just inside the box was once again brilliantly tipped out for a corner by Robinson.