Toyota is working against the clock in an effort to discover the cause of two suspension failures on its cars in Friday's second free practice session.

Both failures were to Jarno Trulli's TF107, and both occurred on the front-right side of the car, and happened at the same part of the track (Turn 8).

Early in the session, the Italian limped back to the pits, his right-front wheel askew following the collapse. Later in the session, the crew having repaired the car, it was a case of deja vu for the hapless Italian when it happened all over again.

The Japanese team now has a race against the clock, needing to find the cause of the problem and ensure that it doesn't happen again.

"My day was cut short because we suffered a problem with my front right suspension early in the second session," said the Italian. "We missed most of the afternoon and it happened again when we went out at the end.

"That is unfortunate," he added, in a masterpiece of understatement. "We will have to investigate the issue tonight. It also means I have had only a very short time to work on set-up changes.

"I've had problems with the rear of the car and I've struggled with high rear tyre wear," he revealed, "so I have a lot of work ahead to catch up tomorrow."

"We have an issue on the front suspension of Jarno's car which is clearly related to this circuit," said chief race and test engineer Dieter Gass. "We have now identified the front upright as the problem area. We have no changes on the parts here and they have been tested and run throughout the season so far. So we need to look into that and understand what has happened.

"As a precaution we kept Ralf in the garage," he added, ending speculation that the German had his own (separate) problems). "This problem has overshadowed all our running today and we are lacking a lot of the information that we were looking for.

"We now need to sit down and change tomorrow's run plan to see how we can make the best out of the weekend."