That suggests that drivers of the speeding cars were stepping on the accelerator rather than hitting the brakes. The vehicles investigated came from a sample in which the drivers said they were braking but failed to stop the car before crashing, the newspaper said, citing unnamed sources familiar with the findings.
Transportation Department officials declined to confirm the report and did not comment. Toyota spokesman Mike Michels said the National Highway Traffic Safety Administration has not shared its findings with the Japanese automaker but said their own findings from investigations of unintended acceleration are consistent with the report.
The black boxes, called event data recorders, are devices that track a number of details about a vehicle around the time of an accident, including which pedals were applied and how fast the car was traveling.
Toyota has recalled more than 8.5 million vehicles worldwide since last fall due to faulty accelerators, floor mats that may trap gas pedals, and brake problems in Priuses, among other problems. The largest problems were due to unintended acceleration, which the automaker has sought to address by fixing the gas pedals and floor mats.
The government has said unintended acceleration in Toyotas may have been involved in the deaths of 93 people over the past decade. The agency has received about 3,000 complaints of sudden acceleration in Toyotas.
Daniel Smith, NHTSA's associate administrator for enforcement, told a panel with the National Academy of Sciences reviewing unintended acceleration last month that the agency had not yet found any defects beyond the two problems cited by Toyota: pedals that can become entrapped by floor mats and sticking accelerator pedals.
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