Kammala wannan jumla: A cikin 1993 da 1994, Coulthard ya yi aiki da Williams Grand Prix Engineering team a matsayin direban gwajin su na hukuma. A tseren wurin zama zama zama samuwa bayan mutuwar Ayrton Senna a cikin
Babban Gasar San Marino ta 1994. Coulthard ya sami kiran waya daga shugaban kungiyar Frank Williams don gwada motar Williams a hanyar Jerez tsawon kwanaki hudu, wanda ya sa ya rasa tseren Formula 3000 a Pau.