Poulsen started his motorsport career in karting in 1985 and was active until 1993 in this sport. Then the Dane came between 1995 and 2007 to write several rallies. Between 1999 and 2006 he competed in three rallies in the World Rally Championship, but could not score points.
2007 Poulsen moved to touring car racing and was 18th in the Danish Touring Car Championship. He also took part in the European Touring Car Cup and finished the season in third place in the Super 2000 classification. In 2008, Poulsen improved with a victory to eleventh place in the DTC and was sixth in the Super 2000 classification of the European Touring Car Cup. In addition, Poulsen debuted in 2008 in the World Touring Car Championship ( WTCC). In a BMW 320si, he participated in three race weekends for Poulsen Motorsport, his own racing team, and on a race weekend for Wiechers -Sport. He scored no points.
2009 started Poulsen Liqui Moly Team Engstler for in a BMW 320si at each race of the WTCC season. While his team-mate Franz Engstler came in 16th place overall, Poulsen stayed with a tenth place as best result with no points. In the Independents' Trophy, he finished sixth. In addition, Poulsen 2009 debuted at the 24 Hours of Le Mans. In a Porsche RS Spyder Evo, he and Emmanuel Collard and Casper Elgaard tenth in the final standings and winners in the LMP2 standings. In the Le Mans Series, he also stepped up to a race and decided there too the LMP2 classification in itself. In the DTC of the racers came into this season only three races, finishing in 18th place overall. 2010 placed Poulsen from the first two race weekends of the WTCC and then entered into a BMW 320si, which was used by his own team, to. Poulsen scored some points races and finished the season with a sixth place as best result in 14th place in the Drivers' World Championship. In the internal Independents' Trophy, he finished in third place. In addition, the racer was seventh in the 2010 Super 2000 Evaluation of the European Touring Car Cup.
2011 Poulsen returned to the Liqui Moly Team Engstler back and was again teammate of Engstler. In the second race in Monza he achieved with his first podium with a third place ranking in the WTCC. In the rest of the season he was a regular in the points, but was not on the podium again. He finished the season in seventh place from the Drivers' Championship, ahead of Engstler, who won a race. The Yokohama Trophy, the score for private drivers, Poulsen won with two points ahead of his compatriot Michel Nykjær. Poulsen announced after the end of the season to leave the WTCC.
- 2007: ETC Cup, Super 2000 ( 3rd place)
- 2008: DTC (11th )
- 2008: ETC Cup, Super 2000 ( 6th place)
- 2008: WTCC
- 2009: WTCC
- 2009: Le Mans Series LMP2
- 2009: DTC ( 18th place)
- 2010: WTCC ( 14th)
- 2010: ETC Cup, Super 2000 ( 7th place)
- 2011: WTCC ( 7th place)