Wheldon began go-kart racing at the age of four but did not take part in competitive racing until he was eight due to age limits. He drove a self-built 60cc kart during the intervals before switching to a 100cc kart later on. Wheldon was sponsored by All Kart owner Bruno Ferrari and his father helped to better his son's driving ability at Rye House Kart Circuit. He won the RAC British Cadet Karting Championship three times in 1988, 1989 and 1990. Wheldon went on to win the British B Junior title driving a Wright chassis in 1992. He was later advised by Mark Rose and Terry Fullerton as he progressed to the international level. Wheldon won the 1995 FIA Formula A World Cup with Fullerton's team. Aged 17, he progressed to car racing, competing in the Formula Vauxhall Junior Championship for Team JLR in 1996, winning the Brands Hatch, Silverstone and Oulton Park races and taking seven top-three results to finish second overall.