WASHINGTON -- The president of Toyota's U.S. operations acknowledged to skeptical lawmakers on Tuesday that the company's recalls of millions of its cars may ''not totally'' solve the problem of sudden and dangerous acceleration.
''We are vigilant and we continue to look for potential causes,'' Toyota's James Lentz told a congressional panel. However, he repeated his company's position that unexpected acceleration in some of the company's most popular cars and trucks was caused by one of two problems -- misplaced floor mats and sticking accelerator pedals.
He insisted electronic systems connected to the gas pedal and fuel line did not contribute to the problem, drawing sharp criticism from lawmakers who said such a possibility should be further explored -- and from a tearful woman driver who could not stop her runaway Lexus.
''Shame on you, Toyota,'' Rhonda Smith, of Sevierville, Tenn., said at a congressional hearing. Then she added a second ''shame on you'' directed at federal highway safety regulators.
Texas Republican Rep. Joe Barton cautioned his colleagues early in the hearing against conducting a ''witch hunt'' and said ''We don't want to just assume automatically that Toyota has done something wrong and has tried to cover it up.'' But midway through Lentz's testimony, Barton said of Toyota's investigation of the problems: ''In my opinion, it's a sham.''
Lentz said the company had not completely ruled out an electronics malfunction and was still investigating causes of the sudden acceleration. Still, ''We have not found a malfunction'' in the electronics of any of the cars at issue, he said.
As to Smith's harrowing story, ''I'm embarrassed for what happened,'' Lentz said. ''I want her and her husband to feel safe about driving our products,'' Lentz said.
At one point in more than two hours of testimony Lentz was asked by Rep. Eliot Engel, D-N.Y., whether there were any new bombshells to come.
''God, I hope there aren't any more,'' he said, while apologizing anew for the problems. ''We stubbed our toe,'' he said.
Three congressional panels are investigating Toyota's problems, which affect a huge number of Americans. Toyota has recalled some 8.5 million vehicles worldwide -- more than 6 million in the United States -- since last fall because of unintended acceleration problems in multiple models and braking issues in the Prius hybrid. It is also investigating steering concerns in Corollas. People with Toyotas have complained of their vehicles speeding out of control despite efforts to slow down, sometimes resulting in deadly crashes. The government has received complaints of 34 deaths linked to sudden acceleration of Toyota vehicles since 2000.
Lentz, who choked up while discussing the death of his own brother more than 20 years ago in a car accident, said he understood the pain.
''I know what those families go through,'' he said.