After the overall victory in the Italian Formula 3 1974 Colombo rose to the formula 2 in the next season. His most successful season was in 1977, where he finished third in Mugello and eighth in the overall standings was.
In the current season he left the formula 2 in order to perceive the one hand, it offered Formula 1 use the German team ATS, where he replaced the Frenchman Jean -Pierre Jarier. For the Belgian Grand Prix at Zolder, he qualified as the 28th of 30 riders for the race; The same came to pass at the Spanish Grand Prix at Jarama. Then he was replaced after only two races by the eventual champion Keke Rosberg. At the Grand Prix of Italy, there was again an opportunity for Colombo when he drove the second Merzario. However, he resigned as 32nd and last from as early as the pre-qualification, while team-mate and chef Arturo Merzario with a qualified 1.7 seconds faster lap for the race. This was the only use of two Merzario race car on a weekend in the history of the racing team.
After his short Formula 1 career Colombo drove two seasons in the midfield Formula 2 and won two third places before the team Sanremo, for which he previously drove himself, served as team owner and manager until the mid- 80s.