Actual spare cars have been banned since the 2008 season. Nowadays, only two cars can be used in the stables at a time. However, the stables are allowed to bring an extra frame to the race venue, around which the car can be rebuilt in the event that the actual car is destroyed beyond repair. Previously, you could have a spare car in the stables, which was always ready to drive in the pit stop. You could also change to a spare car if the start of the race was renewed.
At the 2004 Malaysian Grand Prix Giorgio Pantano became the first driver to experience the new penalty for using the spare car and as such a different engine during a Grand Prix weekend.