Lentz's reiteration of Toyota's longstanding position suggests that top company executives were unmoved by sharp criticism of that stance Monday by House Energy and Commerce Committee Chairman Henry Waxman.

“We are confident that no problems exist with the electronic throttle control system in our vehicles,” Lentz says in 2½ pages of written testimony prepared for delivery to the House panel. “We have designed our electronic throttle control system with multiple fail-safe mechanisms to shut off or reduce engine power in the event of a system failure.”

His testimony adds that the company's “extensive testing of this system” has “never found a malfunction that caused unintended acceleration.”

An advanced copy of Lentz's testimony was provided by Toyota.

Waxman, D-Calif., wrote a letter to Lentz on Monday saying a preliminary review of Toyota documents suggested that the company “consistently dismissed the possibility” of electronic failures as a cause of unintended acceleration.

The company failed to conduct a systematic electronics investigation even after federal regulators sent Toyota a chart in 2004 showing five times as many vehicle speed complaints in Camrys with electronic throttle controls, the letter said.

“Our preliminary assessment is that Toyota resisted the possibility that electronic defects could cause safety concerns,” said Waxman's letter, co-signed by Bart Stupak, D-Mich., chairman of the committee's oversight panel.

In addition, Waxman said an interim study of electronic interference this month by the Exponent consulting firm hired by Toyota's lawyers was “of little value” because of its lack of scientific rigor.

Finally, the letter accused Lentz of making “misleading public statements” about the adequacy of recent recalls aimed at addressing unwanted acceleration.

Lentz said in television interviews this month that Toyota's speed-control problems could be traced directly to floor-mat entrapment of the accelerator and to sticky gas pedals.

Yet Toyota officials had privately told committee staff last month that it was unlikely that sticky pedals would cause unintended acceleration, Waxman's letter said.

Also due to testify at Tuesday's 11 a.m. EST hearing is U.S. Secretary of Transportation Ray LaHood.