After some successes in karting Vietoris moved in 2005 to the German Formula BMW. After he had occupied the 17th place in his debut season, he won in 2006 with nine wins from 18 races, the championship title. In that year he also won the Formula BMW World Final in Valencia. In 2007, Vietoris as a substitute of Nico Hulkenberg in Mexico City for the German team made its debut in the A1GP. Then Vietoris played a season in the German Formula 3 Cup, where he finished fifth overall with two wins. Vietoris peak in 2007, however, was to attend a Formula 1 test day for BMW Sauber, which he had received as a prize for winning the Formula BMW World Final. In the 2007/2008 A1GP season Vietoris started at three race weekends for the German team and won the feature race in Taupo.
2008 Vietoris raced in the Formula 3 Euro Series for Mücke Motorsport. In his debut season Vietoris won a race at the Norisring and finished second in the overall standings to sixth place and was behind Hulkenberg second best German. 2009 denied Vietoris for Mücke Motorsport his second season in the Formula 3 Euro Series and had chances to win the championship. He won four races and took the only driver in every race in which he had started in the points. A race weekend before the end Vietoris had to be content with the runner-up title behind Jules Bianchi. In addition, he was the best German pilot in the Euro Series.
In the 2009/2010 GP2 Asia Series season Vietoris went for DAMS at the start. After he had made a good start with a victory in the sprint race of the first race weekend at the Yas Marina Circuit in the season, he drove in the course of the season, a no further points and eventually finished in tenth place in the overall standings. 2010 Vietoris went for Racing Engineering in GP2 series at the start. After he had at the beginning of the season starting difficulties and in contrast to his team -mate Dani Clos not rode along the front, he stood over the race weekend at the Hungaroring in both races in second place on the podium. During the sprint race at Monza Vietoris finally achieved his first victory in the GP2 series. After he was unable to attend on the last race of the season because of an appendicitis, he finished at the end of season ninth overall.
2011 denied Vietoris for Racing Engineering his second season in the GP2 series. After an accident on the first weekend he paused the next two race weekends because of severe headaches. On the fifth race weekend at Silverstone, he scored his first points in second of the season. Over the next two race weekends is Vietoris sat again in the limelight. At the Nürburgring he works in the rainy sprint races of 23 on the grid to fourth place forward. At the Hungaroring, he led the sprint race at first, turned, however, the onset of rain and collided with a counterparty. Thus his front wing was damaged and he came out of the points to the finish. A race later, the main race at Spa- Francorchamps, he led the race again until the rain started. This time, however, he retained the lead and scored his first win of the season. At the season finale at Monza was followed by another victory. The season he finished in seventh place in the drivers' standings. It was thus a position ahead of his teammate Clos, who was unlike Vietoris at every race at the start. Parallel to his GP2 commitment went Vietoris Persson Motorsport in 2011 for an AMG -Mercedes C-Class in the DTM at the start. In the eighth race in Oschersleben, he scored his first points in fifth place. At the end of the season he was 14th in the overall standings. His teammates Renger van der Zande and Susie Wolff remained without points.
2012, Vietoris decided to completely change in touring car racing. In the DTM, he received a cockpit at the Mercedes - HWA team. At the first race he achieved his best DTM until then placement with a fourth place. This he could not be repeated in the rest of the season. With four top - 10 finishes Vietoris was twelfth in the championship and third-best Mercedes driver. 2013 remained Vietoris at HWA in the DTM. Already in the season opener at the Hockenheimring, he scored his first podium placement with a third place. On the Euro Speedway Lausitz, the Norisring and the Nürburgring he repeated this result. At the end of the season he finished fourth overall.
- 2000-2004: Karting
- 2005: German Formula BMW ( 17th)
- 2006: German Formula BMW (Master)
- 2007: A1GP
- 2007: German Formula 3 ( 5th place)
- 2008: A1GP
- 2008: Formula 3 Euro Series ( 6th place)
- 2009: Formula 3 Euro Series (2nd place)
- 2010: GP2 Asia Series (No. 10)
- 2010: GP2 Series (No. 9)
- 2011: GP2 Series (No. 7)
- 2011: DTM ( 14th place )
- 2012: DTM ( 12th place)
- 2013: DTM ( 4th place)