Toyota's car has a series of problems, according to the team

Technical director Mike Gascoyne, who joined the team in December, said the car would be "totally repackaged" for the San Marino race on 25 April.

"We haven't concentrated enough on getting weight low in the car," Gascoyne told Motorsport News.

"We're also planning an even bigger update for Silverstone (on 11 July)."

Gascoyne, who arrived from Renault after the design of the new Toyota was finished, added that some new parts for the car would be ready for the next race, in Malaysia next week.

Drivers Cristiano da Matta and Olivier Panis finished 12th and 13th in last weekend's Australian Grand Prix after being uncompetitive all weekend.

Da Matta said: "The car's performance was not good at all but at least we are under no illusions now.

"We know where we are and we have to work really hard to make progress up the field."

Panis added: "We are far away from the top teams and there is a long road in front of us."

Gascoyne said there was no problem with Toyota's engine, reckoning it to be a "world championship winning engine".

He added: "Our main problems are with the chassis and, in particular, its aerodynamics but we already have programmes in place to rectify the situation and everyone is working flat-out to get us where we should be, which is at the front of the grid."