After his sole F1 race in 1977, Giacomelli entered five races in 1978 for McLaren, when his Formula Two commitments allowed. He achieved his best finish, of seventh place, in the 1978 British Grand Prix. After winning the European F2 title, he switched to Alfa Romeo for their return to building F1 cars in 1979. Alfa only entered their 177 and 179 cars in a handful of events that year, and Giacomelli could only achieve a best of 17th place in the 1979 French Grand Prix.

However, the following year the team looked more promising. Giacomelli earned a surprise 6th place qualifying position for Alfa Romeo at Brands Hatch for the 1980 British Grand Prix. Giacomelli posted a third-place qualifying time for the 1980 Italian Grand Prix at Imola. He won the pole position for the 1980 United States Grand Prix at Watkins Glen, New York in his Alfa Romeo. In 1981, the car was somewhat more reliable, with Giacomelli being a classified finisher in eight of the season's 15 races. For 1982 Alfa introduced their new Alfa Romeo 182 to replace the ageing 179, however, the new chassis proved to be unreliable in the first half of the season. In the second half, it was reliable enough to allow Giacomelli to finish all but two of the races, however, the year only yielded one points finish for him, with a fifth in Germany.

Alfa recruited Mauro Baldi to partner Andrea de Cesaris for the 1983 Formula One season and Giacomelli joined Toleman. Giacomelli was outperformed by his teammate Derek Warwick, though he did manage to pick up a final F1 point at the 1983 European Grand Prix at Brands Hatch.

Giacomelli was the test driver for the Leyton House March team in 1988 to 1990. In 1990, Giacomelli returned to F1 with the Life outfit, taking over from Gary Brabham (who left the team two races into the season). The car, saddled with an ineffectual and fragile W12 engine, struggled to get within 20 seconds of the pole time at many circuits and Giacomelli failed to even get out of pre-qualifying at any of the 12 Grands Prix he contested with the team. At the Portuguese Grand Prix the team reverted to a more conventional Judd V8 engine, but the car had not been adapted for the new engine and the team were unable to properly fit the engine cover, leading to them pulling out of the event without completing a single lap. When Giacomelli was able to drive the Judd-powered car in Spain he found himself 18 seconds off the pace despite the new engine. With money in short supply and few hopes of improving their desperately noncompetitive package the team folded before the final two races of the season, ending Giacomelli's F1 career.

 1977 - 1990
Grand Prix: 82
Drivers Championships: -
Victories: 0
Podiums: 1
Pole Positions: 1
Fastest Laps: 0
Career Points: 14

Activity: 1984 - 1985
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