Theissen: BMW have not given up on 2008

Former world championship leader Robert Kubica has scored just seven points in the last four races and the team have also slipped to third in the constructors' championship, but Theissen says his team have not yet settled for best-of-the-rest this season.

"We have underperformed certainly in Budapest and maybe in the races before as well," said Theissen when asked by autosport.com whether the priority was now to focus on staying ahead of Toyota and Renault. "We still want to catch the two in front of us.

"We were nowhere in Hungary. It was two or three issues - the main one being tyres, or the use of the tyres. That can be put down to tyre pressures. We just screwed up in terms of tyre pressures."

Kubica believes that getting the tyre pressures wrong cost a potential podium finish in Hungary, but is hopeful that the problem will not be repeated.

"Hungary was quite disappointing - we had big tyres pressure problems which had a big influence on the grip level and the balance of the car," he said.

"This kind of problem shouldn't happen in F1 in general, but unfortunately we did have some operational problems and it cost us a lot of points. It also cost me 70 laps of the Hungarian Grand Prix with a lot of effort to finish the race.

"We were miles off the operating window - but we will try to improve and I hope this kind of thing won't happen again."

Theissen believes that despite Kubica voicing his difficulties in getting the tyres into the correct operating window this year it is not a problem unique to BMW Sauber.

"This is quite normal," said Theissen. "These tyres are very sensitive to pressures. It might be that Robert communicates these developments whereas other drivers don't, but everyone is dealing with the same problem.

"Tyres are a key factor in lap-time and the right tyre pressures change quite a lot depending on the ambient conditions, track conditions and the way you change the car. It is a difficult thing and we have learned we have to use a lot of time for getting that right."

Heidfeld is also confident that the team will be able to re-establish themselves as the third strongest on the grid after losing out to Toyota and Renault in recent races.

"It depends very much on the circuit," he said. "Some of the teams behind us have made some good steps, especially Toyota and also Renault and at times Red Bull. But even for Ferrari it seems to have been more up and down than it was in the past.

"Budapest was not our strongest race, but just two weeks prior at Hockenheim where the car was not that different I set the fastest lap. So you cannot say our car is slow."