saw Sauber 's worst Formula One season in terms of points . They had a promising driver lineup with Heinz Harald Frentzen and Johnny Herbert , a revised C15 car and a new V10 engine from Ford . 1996 saw Sauber 's worst Formula One season in terms of points despite a promising driver lineup in Heinz Harald Frentzen and Johnny Herbert , a revised C15 entrant and a new V10 powerplant from Ford .