After reviewing more than 150 complaints, the agency has declined to push for a recall.
The National Highway Traffic Safety Administration has closed its investigation into claims of unintended acceleration with the Toyota Corolla.
The agency last year received a petition from the driver of a 2010 Corolla who blamed "low-speed surging" for causing a minor accident while parking. The owner claimed to have found 163 similar complaints in the NHTSA database.
"NHTSA conducted a technical review of the material cited and provided by the petitioner, material Toyota submitted in response to a NHTSA formal request, interviews with complainants and manufacturer representatives, as well as the results of testing of the complaint vehicle," the agency notes. "NHTSA has concluded that further investigation of the issues raised by the petition is not warranted."
In its denial, the NHTSA cites a 1989 study that concluded many of the sudden-acceleration incidents are simply related to "pedal misapplication" rather than vehicle defects. A follow-up study, specifically related to unintended-acceleration issues in Toyota vehicles, led to recalls to prevent floor-mat entrapment, "sticking accelerator pedals" and pedal interference, however the study found no inherent flaws with the software that controls the electronic throttle-control system (ETCS-i) in the Corolla that was the subject of the latest investigation.
"NHTSA and NASA released released reports detailing the results of this study in early 2011, concluding that incidents alleging low-speed surges during brake application were most likely related to driver pedal misapplication and were not associated with an electronic or software defect in Toyota's ETCS-i system," the petition rejection adds.
The agency also observes that the large number of unintended-acceleration complaints for the Corolla were posted in 2009-2010, coinciding with publicity surrounding the legitimate recall for similar behavior. The trend is viewed as further evidence that complainants likely misinterpreted their own pedal mistakes as a defect.