Malenfant began his career in Prost GP with the Ambrose-Milan Autosport team. After the entire team missed the first race of the season at Adelaide, Malenfant qualified on the front row in Mexico, next to his teammate Joey Alliot. He was in third place when his brakes failed with six laps to go. The next race in Canada, Malenfant qualified 4th, behind his teammate once again. During the race, he spun at the Wall of Champions while in third, but still managed to hold his position. Malenfant raced his way up to second place following his spin. In the closing laps, Alliot, the race leader, had an engine failure, promoting Malenfant to the lead. Malenfant maintained this lead for the rest of the race and won his first race in only his second start.
San Marino was much worse for the Frenchman. He qualified a lowly 10th, and made some progress through the race. His race ended prematurely with an engine failure. His luck improved in Spain, where he qualified and finished in 3rd, after a brief stint in the lead. He qualified 4th in Austria, but later retired from the race. Engine failure struck again in Scotland, and he retired after only 19 laps.
Malenfant acquired his first pole of the season at the British Grand Prix. He had battled for the lead almost the entire race before retiring from 3rd with 2 laps to go. Malenfant could not repeat his qualifying performance next race, and only qualified 9th for the Grand Prix of England. His race ended unceremoniously with an engine failure.