Jarno Trulli says he has been baffled by the inconsistent performance of some Formula 1 teams this season as a result of their problems handling Bridgestone's tires.
"This year we have had a lot of troubles to predict and also during the weekend we have had tire handling problems, warming them up, and not very good consistency so far," said the Toyota driver. "The performance is good but sometimes we could not find an explanation on one car or another."
He added: "For me at Silverstone, I had an incredible qualifying and the race was terrible. Even though I scored points it was such a difficult race, really, really bad, far off from where I should have been, and this is driving us mad a little bit. We don't understand, we can see the area but we cannot understand why we have troubles.
"This is what is happening this year, and honestly not only to us. It is difficult to explain and difficult to talk about, we are investigating but it is not an easy issue to solve."
Teams have complained that the difference between the two types of tires used during races was too big, usually making one of the compounds very hard to work with during GP weekends. Bridgestone announced earlier this month that it will reduce the disparity between the two compounds in the upcoming four races. Trulli believes that decision will help reduce the problems, but he thinks there is more to his team's problems than just that.
"We have all been complaining about this, and the rest of the season will probably be much better because of the decision by Bridgestone, but I believe this cannot be the explanation, because if you have a problem you usually have a problem through the weekend, you don't have it only on one session, or any more in another or the race.
"I cannot blame [Bridgestone] for the problems we suffer. [But] for sure we can say that the tyre choice made up until now was not necessarily right, in terms of positioning the tires."
The Italian driver reckons Toyota has a fight in its hands to stay in third place in the championship, with Williams and Ferrari edging closer.
"Williams is a threat to us, at the moment they are running very well and their car is running pretty good, and Ferrari is coming back, but we have the chance to fight for third in the Constructors' Championship and this is the most important thing, after that the aim is to close on the gap in front."