Toyota yesterday hit back at allegations that defective electronics are behind the recall of 8.5 million of its cars in recent weeks.
The world's biggest car maker re- iterated its claim that the issue with sticky accelerator pedals and mis-fitting floor mats was purely mechanical.
It said independent research from Stanford University showed that the malfunction can only be created by re-wiring the entire electronic control systems, which has the same effect of producing uncontrolled revving in other makes of car.
The investigation was launched after an engineer, who originally appeared on ABC News, told last month's US Congressional hearing that faulty electronic systems could be behind the unintentional acceleration problems that are blamed for 19 deaths.
Toyota hit back at ABC News yesterday, claiming that the report was "staged", and brought in its own experts to rebut both the engineering and the editing of the film.
Not only could such massive re-wiring not occur "naturally", but the ABC News film, which showed engineer David Gilbert from an Illinois University shorting the electronics and making the Toyota speed up, took place when the car dashboard lights show it was actually parked, claimed Toyota.
ABC says multiple demonstrations of the test were taped and the results of them were all "comparable".
Analysts are predicting the wave of recalls – affecting accelerator pedals in a range of models, and also a glitch in the anti-lock braking systems on its hybrid Prius – could cost Toyota as much as $5bn (£3.3bn) in lost business and litigation. Nearly 90 class-action law suits have already been filed in the US claiming lost value because of the recall, and alleging that Toyota made the problem worse by not acting swiftly.
Akio Toyoda, Toyota's embattled chief executive, has been on a charm offensive in recent weeks in an effort to repair the damage caused by both safety fears and the public perception that the company did not react fast enough to complaints. After an abject apology in the US Congress, he flew to Beijing the following week and has also addressed thousands of Toyota dealers and suppliers in his native Japan.
So far Toyota's sales have not fared as badly as feared. The group's market share in the US, where the worst of the problems surfaced, only slipped by 1.3 percentage points in January and the company is still on course to report an ¥80bn (£593m) profit for the financial year to March, compared with last year's ¥437bn loss, its first in nearly six decades. A recall cost of ¥180bn is already factored into the estimates.
Drive a Toyota? Head for the hills
*As Toyota tries to shore up its damaged reputation, drivers' lurid reports of high-speed malfunctions continue to surface.
San Diego resident James Sikes, 61, said his Prius took off at 90mph after the accelerator became stuck after overtaking another car on a California freeway. "I pushed the gas pedal to pass a car and it did something kind of funny," Mr Sikes said. "It jumped and it just stuck there."
Mr Sikes only escaped unharmed after a police patrol shepherded him to a hill to help cut his speed, and then directed him to pump his brakes. Once the car's speed was down to a more manageable 50mph, Mr Sikes turned off the engine, and it eventually rolled to a stop.
"I was trying the brakes," Mr Sikes said of his experience. "But it wasn't stopping."