 Di Grassi made his car racing debut in 2002, driving in the Formula Renault 2.0 Brazil, finishing the season with two victories, and placed seven points behind the series victor Sérgio Jimenez.In 2003, he switched to the Formula 3 Sudamericana and joined the Avellone team.Di Grassi took one victory and stood on the podium eleven times, en route to second in the championship, behind the more experienced Danilo Dirani, despite missing the season's final six races due to him injuring his neck in an accident he sustained in Curitiba.