Sauber endured a difficult start to the Korean Grand Prix weekend with Kamui Kobayashi and Sergio Perez both suffering in Friday practice.
Kobayashi went into practice on a high after his first podium finish in F1 a week earlier in Japan, but he struggled for pace in Yeongam and could only managed 14th on the timesheets, with the Japanese racer admitting his low-fuel speed was a cause for concern.
“We completed a huge programme with my car today but I'm not really happy yet,” he said. “On high fuel it doesn't look bad actually but on low fuel I'm struggling a lot. We have to find out how we can improve and I think we will find solutions.”
Kobayashi was at least able to complete his programme, unlike team-mate Sergio Perez after a more troubled day for the Mexican.
Although the opening session passed without issue, Perez was then forced to park up when a technical issue forced him to pull off in FP2 – leaving him down in 15th as a result.
Despite that however, Perez said he remained confident about his chances for the remainder of the weekend.
“For me the first session went quite well but then in the second session I lost a lot of track time because of a technical problem,” he said. “I just had no engine power anymore and had to stop on the track. That was why I could not complete my programme and haven't done any long runs on either tyre compound yet so it is too early to say what we can do here. Nevertheless I am very confident for the remainder of the weekend.”
Head of track engineering Giampaolo Dall'Ara admitted there was room for improvement.
“Unfortunately we have lost half of the second session on Sergio's car because of a problem with the engine management,” he said. “With Kamui's car we didn't have any reliability issues but performance-wise we have to improve. We need to get a better understanding of a few things and decide what to do. Generally speaking the soft tyre compound is definitely the better one for us. We have to look deeper into the data to find solutions on how to manage the super-softs.”