Although Toyota has apologized to its customers and begun a program to repair a sticking accelerator that led to both a recall and a halt in production, the company's problems may not be over, with the U.S. Department of Transportation investigating defective electronic controls on key models.

In a statement, Transportation Secretary Ray LaHood said, "We're not finished with Toyota and are continuing to review possible defects and monitor the implementation of the recalls." The focus of the probe appears to be an attempt to link unintended acceleration issues to defective electronics rather than the mechanical issue cited by the company.

A Toyota spokesman, John Hanson, quoted in a story for Automotive News by Neil Roland said, "After many years of extensive testing, we've found no evidence of an electronic problem that could have contributed to unwanted acceleration. We've investigated many times and found no evidence to point to."

Toyota pins the acceleration issues on problems with interference from floor mats and on a sticking pedal, correctable by the installation of a steel shim to reduce friction on the unit. Toyota vice president Shinichi Sasaki, the executive in charge of quality, denied the existence of related electronic malfunctions.

In an interview in Japan Sasaki said, "We have not come across any case in which we have found a malfunction. But if any additional reports arise, we will conduct testing using all technology at our disposal."

Jim Lenz, President of Toyota Motor Sales USA, in a full-page advertisement running in American newspapers on Tuesday, February 2 said, "We have launched a comprehensive plan to permanently fix the vehicles we've recalled because in rare instances, accelerator pedals can, over time, become slow to release or get stuck. We know what's causing this and what we have to do to fix it."