Born in Kuala Lumpur, Yoong began racing when he was 18 and scored his first victory in the Formula Asia International Series in Zhuhai, China in 1994. The following season he scored eight wins in Formula Asia and it was decided that he would go to Britain to pursue his dream of getting into Formula 1. He raced for two years in the British Formula Renault series and then moved to Formula 3 in 1998 with Alan Docking Racing. His money ran out in 1999 despite the fact that the Malaysian government announced that it would be helping him to get to F1. After trying his hand at Italian Formula 3000 he did some races in the International Championship but this ended with a huge crash in Eau Rouge corner at Spa. He did not do any international racing in 2000 but came back in 2001 in the Formula Nippon Championship in Japan, racing for the Le Mans Company.