After a trouble free first free practice session before the Korean Grand Prix at Yeongam, the second 90 minutes session on Friday afternoon didn't go so smoothly for the Sauber F1 Team. Sergio Perez had to stop on track after only eleven laps due to an engine management problem. Kamui Kobayashi continued driving but wasn't happy with his car.

Kamui Kobayashi: "We completed a huge programme with my car today but I'm not really happy yet. 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."

Sergio Perez: "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. 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."

Giampaolo Dall'Ara, Head of Track Engineering: "Unfortunately we have lost half of the second session on Sergio's car because of a problem with the engine management. 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."

Check out our Friday gallery, here.