Sudden Unintended Acceleration was defined by a 1980s National Highway Traffic Safety Administration (NHTSA) report to be:
"Unintended, unexpected, high power accelerations from a... low initial speed accompanied by an apparent loss of braking effectiveness."
Unintended Acceleration has been blamed on many issues including driver error, a sticky accelerator pedal, incorrectly fitting floor mats, and a faulty electronic control system. It is likely that all of these issues have caused an unintended acceleration incident over the span of multiple car manufacturers since 1980.
Incidents before the year 2000 were noted to have most likely come about immediately when the car was shifted from park into drive. Recent defects, however, usually result in unintended acceleration when the car is already in motion. Survivors recall their cars accelerating at full speed and the car not responding to the brakes when applied.
Early incidents of unintended acceleration in the 1950s would happen in GM cars when drivers would accidentally select L in the transmission when they intended to select Reverse. Again in the 80s, many Audi drivers reported their car suddenly lurching forward from a parked or stationary position, but it is suspected that many of these reports were due to driver error, as the brake and gas pedals were situated closer to each other than the average distance on an American car.
Within the last 20 years however, sudden acceleration has occured for a variety of different reasons, most notably in Toyota cars, but also in cars made by other manufacturers such as Ford. In 2008, the NHTSA ran one of several investigations into unintended acceleration in Toyota vehicles, and found that a plastic piece from the driver-side dashboard could come loose and prevent the gas pedal from coming back into its' original state from being depressed. Similar results were seen with floormats that had been moved out of place. In 2009, a Toyota dealership witnessed a car experiencing unintended acceleration without a floor mat, meaning that there was an issue with the electronic control system.
Over the years, many SUA accidents have been caused by all of these factors, but it is thought that the electronic control system issue was the underlying cause of the majority of incidents.
When your car accelerates and pressing the brake does nothing to slow the car down, your natural reaction might be to panic. Try to remember the following steps:
Make sure your foot is on the brake and keep it pressed down:
Most modern cars will have a brake that overrides the accelerator, but if you happen to have an older car without this feature, you may still be able to slow the car down with enough force on the brake pedal.
If the car is slowing down when you are braking but it has not stopped:
- Automatic Transmisison: Put your car into the lowest gear possible.
As soon as you've made sure that your foot is firmly on the brakes, put your car into the lowest gear possible. In an automatic transmission car, this will be the "L", or "1" gear. An automatic transmission will utilize engine braking to slow the car down in addition to the brakes being applied. Continue pushing the brakes until the car comes to a complete stop or you are able to put the car in neutral and pull over to the side of the road.
- Manual Transmisison: Downshift slowly and safely.
If your car is slowing down gradually but you need it to slow down more quickly, downshift through every gear, making sure your engine has time to slow the car down safely without shifting too soon and causing your car to skid. If you have an open road you may just want to put the car in neutral and let it coast to a stop.
If the brake is not working and the car is still accelerating:
If you are coasting but you still need to slow down suddenly, put the vehicle in park:
Unfortunately this will most likely destroy your transmission, but if the previous steps have not slowed down your car enough, this may be your last option for keeping yourself and your passengers safe.
After the GM and Audi incidents of sudden acceleration, which were both determined to be caused by driver error, incidents from the 90's onward involved multiple makes of cars - most notably Toyota, but also from Ford and Kia.
One of the first Toyota incident occurs in 2002 with a complaint of a Toyota Camry experiencing acceleration when the brakes were fully depressed. Many reported incidents followed, which led to multiple investigations by the NHTSA. Most of these investigations however were closed citing inconclusive evidence. Eventually though with enough evidence, the problem of sudden acceleration was finally taken seriously. Multiple car companies were brought to court for wrongful death cases, and in 2014 the Department of Justice fined Toyota $1.2 billion dollars for misleading their consumers regarding their dangerous cars. You can read about the timeline of the Toyota scandal here.
The following are some of the more notable incidents of sudden acceleration:
December 1998: Denise Keenan and Blake McCarty are killed when a Ford police vehicle accelerates through the crowd at a 'Holidazzle' parade in Minneapolis. Investigators find that the officer responsible had pressed the accelerator instead of the brake accidentally, but that the accident could have been prevented if the shift-lock, which prevents the car from shifting into drive if the foot is not on the brake pedal, was functioning properly. The shift-lock was found to be disengaged due to an electrical error that occured when the van's police lights were flashing.
September 2007: A 2005 Camry stars accelerating coming off of a highway in Oklahoma. Tire skidmarks show that the driver was braking and the account of the driver asserted that the main brakes were used in addition to the parking brake. The car continued to move and hit an embankment, injuring the driver Jean Bookout and killing her passenger Barbara Schwarz.
August 2009: Noriko Uno was driving in Southern California when she was struck by a car rolling through a stop sign. Immediately, her car began accelerating without being able to stop and resulted in Uno traveling the wrong way on a street accelerating up to speeds close to 100 miles per hour. Uno collided with several objects and was killed upon impact with a tree. Witnesses say they observed Uno looking terrified as she tried to steer out of the way of traffic and it was determined that Uno's foot was lodged underneath the brake pedal and she was unable to brake effectively. This was the first unintended acceleration trial to go to court against Toyota, with the claim that if Toyota had installed a brake override in the Camry, Uno's attempts to brake would have put the engine in neutral and she would have been safe.
August 2009: On the same day as Noriko Uno's death, a family of four experience their 2009 Lexus ES350 accelerating without pressing the gas pedal. The driver was California Highway Patrol officer Mark Saylor, who had many hours of experience on the road and was unlikely to make the mistake of pressing on the gas pedal instead of the brakes. A 911 call was recorded of either Saylor or his brother reporting that the brakes weren't working and that the car was not slowing down. The call ended when the car hit an embankment and crashed, killing all four passengers. This accident prompted Toyota to recall 3.8 million cars so they could replace the floor mats which allegedly made the accelerator pedal stick.