Toyota's petrol-electric hybrid is one of the most complex cars on the road today, combining an electric motor, a four-cylinder internal combustion engine and a myriad of electronic sensors and computer software to keep the whole show running seamlessly. It's not hard to fathom that some of the cars could have bugs residing within, and according to accounts from select owners, these bugs are down right dangerous.
Stories of cars accelerating by themselves are not unheard of. One Prius owner with only 600 miles on the clock told ConsumerAffiars of his car experiencing "uncontrollable acceleration," and another reported that after hitting a large bump in the road, traction control flared up before the brakes cut and the car started to lunge forward.
When questioned, Toyota service technicians dismissed the claims as either driver error or a problem with the floor mats jamming the accelerator pedal. Try telling that to the handful of drivers who've been taken for a ride in a Prius with a mind of its own.
[Source: The Truth About Cars]