1991 and 1992: Ligier

After his F3000 championship victory in 1990, Comas was selected to drive for the Ligier F1 team in 1991. The Ligier JS35 with its Lamborghini engine proved uncompetitive throughout the season. Comas failed to qualify for the race on his first attempt in Brazil, achieved his first finish with 10th at Imola, and achieved his highest finish of the season with 8th in Canada, scoring no points during the season. Although he failed to qualify on two other occasions and suffered a spectacular crash at Hockenheim, he generally compared well with more experienced teammate Thierry Boutsen who also failed to score any points. Early in 1992, Comas's place in the team was briefly threatened by Alain Prost who tested the team's new Renault-powered car with a view to driving for, and possibly buying the team. Ultimately Prost chose not to proceed, and Comas retained his drive alongside Boutsen for the season. The 1992 car, the Ligier JS37 seemed promising, a brand new design featuring the race-winning Renault V10 engine, but it proved to be only inconsistently competitive. Comas scored his first career F1 point with 6th place in Canada, scored 5th at Ligier's home race in France and a further point in Germany during a mid-season revival of the team's fortunes. With four points, he was generally faster than and outscored Boutsen, and finished 11th in the Driver's Championship. At the 1992 Belgian Grand Prix Comas was involved in a severe accident at the Blanchimont corner during Saturday qualifying. Left unconscious in his car beached in the middle of the track with the engine still running at its rev limiter, Comas was rescued by Ayrton Senna who stopped his own car and ran to help Comas, by shutting off the car's screaming engine (which was still pumping fuel and could have blown at any moment starting a fire), and holding the Frenchman's head in a stable position until medical assistance arrived.^[1] Comas credited Senna with saving his life.

1993 and 1994: Larrousse

Comas was not retained by Ligier for 1993. Instead, he signed with the small Larrousse team, running the LH93 chassis powered by Lamborghini V12s. The car was uncompetitive, Comas retiring from half the 16 races of the season, and scoring only one point for 6th at Monza.

Retained by Larrousse for 1994, Comas drove the LH94 car, now powered by more reliable Ford HB engines. Comas scored a point for 6th at the Pacific Grand Prix, and benefited from the retirement of many other cars to take another point at Hockenheim. This was both his and Larrousse's final F1 points finish. For the last race of the season in Australia, Comas relinquished his seat to make way for Jean-Denis Delétraz who brought more funding to the team.

At the 1994 San Marino Grand Prix due to a radio miscommunication Comas was released onto the track during the red flag after Senna had crashed, arriving at the Tamburello corner where he met the workers and vehicles, including an aid helicopter which had landed at the scene. Having had to brake hard to avoid hitting either marshals, their vehicles, or the helicopter Comas declined to participate in the restart of the race, after witnessing medical staff treating the mortally-injured Senna.