Toyota's president . He'll likely be asked about an internal company memo that shows the car manufacturer saved $100 million in 2007 by to narrow their investigation. The regulators agreed to just a limited recall.
Congress already has thousands of pages of Toyota documents to sift through, but CBS News obtained one internal document that could be devastating to Toyota's claims that electronics aren't at issue.
CBS News has learned that as early as 2005 Toyota engineers were redesigning software in response to complaints of cars surging unexpectedly, reports CBS News Correspondent Sharyl Attkisson.
That could be crucial because publicly Toyota has insisted for six years - through eight federal investigations - that electronics are not to blame when its cars surge, sometimes out of control.
Instead, Toyota faults drivers, floor mats and - more recently - sticky gas pedals.
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The internal document obtained by CBS News appears to contradict Toyota's claims. Dating back five years, it tracks Toyota's "monthly progress" in addressing "Surging back and forth sensation at constant throttle" in 2006 Lexus hybrids like the RX400h model. Toyota engineer Masahiro Ikeda notes surging "between 39-44 miles per hour" and "at 70 mph." The "fix"? Redesigning software for the car's Electronic Control Unit or ECU. "Software planned for first week in August," the internal document says.
In a response on Monday, Toyota acknowledged the internal reports of surging and the software fix. But a spokesman said it wasn't a problem of unintended acceleration; it was a more subtle rocking sensation that caused a seasick feeling and was fixed for customer comfort.
Experts say a glitch in Toyota's "Electronic Throttle Control System" would be much more expensive and problematic than faulty floor mats.
Two sensors measure the position of the accelerator pedal under the driver's foot.
"If it's an electrical problem, which I believe it is, then it really means that we have to question the whole way that the systems are constructed," electrical engineer Antony Anderson said.
So far, Toyota has recalled 7.475 million vehicles for supposed sticky pedals and floor mats. But those vehicles - and millions more on the road - have the electronic throttle control system at issue in the company's own report in 2005.