Toyota, using results of testing it commissioned, will seek to rebut allegations that its cars' electronics are at fault for unwanted acceleration.

A professor's experiment, demonstrated in an ABC News report and described in congressional testimony, alleged that Toyota Avalon's electronic controls were vulnerable to short circuits. Toyota's report today says the experiment's "highly artificial conditions" would not occur in real use.

The embattled automaker also faces a demand from unsatisfied House Democrats that it provide this week engineers or managers with "personal knowledge" of its efforts regarding unintended acceleration.

The House Energy and Commerce Committee, in a letter to Toyota's U.S. sales chief, said that there is "an absence of documents" to show Toyota has thoroughly investigated whether electronics are causing unintended acceleration. The panel held a hearing about Toyota on Feb. 23. Toyota President Akio Toyoda told a different House committee Feb. 24 he is "absolutely confident" there is no electronics problem.

Adding pressure, however, is that the government said Thursday that it has "more than 60" reports from Toyota owners about unintended acceleration in cars recalled and repaired by Toyota for what it says could cause the problem: 2.3 million vehicles in the U.S. to fix gas pedals that could stick and 5.3 million over floor mats that might jam pedals.

USA TODAY found at least 14 new acceleration complaints filed Friday and Saturday from owners who had already had their vehicles fixed under the recall.

The National Highway Traffic Safety Administration is vowing to order Toyota to make more repairs if the automaker's current remedies are found lacking. In an unusual move, NHTSA says it is contacting each individual who's made a new complaint after a dealer made recall repairs.

Among new complaints: An owner from Meridian, Miss., told NHTSA Saturday that since the recall repairs were made last month on the person's 2006 Toyota Avalon "now my vehicle acceleration malfunctions every time I drive it." The owner (NHTSA does not reveal names) reported nearly hitting another car at a stop sign because of the problem.

Toyota today will present the technical report it commissioned by testing firm Exponent in a Web briefing for journalists intended to refute allegations that its electronic controls can go haywire. The report deals with an experiment by David Gilbert, an associate professor at Southern Illinois University, that showed the wiring in a Toyota Avalon could malfunction in a way that creates unintended acceleration.