Discovered by legendary club manager Guy Roux, who was vacationing in the island, he moved to AJ Auxerre's youth academy in 1982, aged 16, going on to amass nearly 400 official appearances for the club in nine full professional seasons and making his Ligue 1 debut on 25 September 1984 in a 3–1 home win against Stade Brestois 29.

During the 90s, speedy Vahirua was part of a solid team whose attacking unit also included Gérald Baticle, Christophe Cocard and Corentin Martins.

He left the team in 1995 – precisely the year they would go on to achieve a historic double – with only the 1994 edition of the French Cup to his credit.

Vahirua earned his first cap for France on 21 January 1990, in a friendly home with Kuwait (1–0), and scored his only goal in another exhibition game, against Belgium in preparation for the UEFA Euro 1992 (3–3), on 25 March.

Summoned for the final stages by Michel Platini, the coach who also gave him his debut, Vahirua played twice in an eventual group stage exit, and was also part of the nation's infamous 1994 FIFA World Cup qualification campaign, in which they lost their last two home matches.