Toyota Motor Corp said on Wednesday its investigation of nearly 2,000 cases of unintended acceleration had found no problem with its electronic throttle system, and that driver error was to blame in some cases.

The world's top automaker made the statement after a Wall Street Journal report that early results of the US government's analysis of dozens of data recorders from Toyota vehicles suggested that some drivers were at fault in cases of sudden acceleration.

Citing people familiar with the unreleased results of the US Department of Transportation's tests, the paper said some drivers who said their Toyotas or Lexuses surged out of control might have pushed the accelerator when they meant to brake.

The Department of Transportation would not confirm the report.

Toyota said the National Highway Traffic Safety Administration (NHTSA) had not reported details of its findings to Toyota. It said Toyota had also concluded that "pedal misapplication" was shown to be the cause in some cases of unwanted speeding.

Toyota has provided NHTSA with 10 event data recorders, and four recorders to Canadian authorities, and all of its findings from the 2,000 on-site inspections, Toyota spokesman Mike Michels said.

No conclusion expected for months

US regulators are investigating whether there are problems with Toyota's electronic throttles, and whether any glitches have played a role in unintended acceleration complaints. As many as 89 crash deaths have been reported since 2000 as possibly being linked to unintended acceleration in Toyota cars.

NHTSA has enlisted space agency experts to look at the software-driven throttles. The safety agency will also tap the expertise of an independent scientific panel, which is studying the matter separately.

Conclusions are not expected for months.

In years of reviewing unintended acceleration in Toyota vehicles, NHTSA has never found a link to electronic throttles.

Toyota maintains its throttles are sound and blames unintended acceleration on floormats that can jam the accelerator pedal and pedals that would not spring back as designed.

Those equipment and mechanical problems were behind the worldwide recall of more than 8 million Toyota and Lexus vehicles in October 2009 and January 2010 for unintended acceleration.

Toyota faces a potential civil liability estimated at more than $10 billion from lawsuits sparked by complaints of runaway cars and trucks.

Shares in Toyota rose 4.6 per cent on Wednesday morning in Tokyo, in line with a strong rise in other Japanese auto stocks.

"It's basically the weaker yen," said Hiroaki Kuramochi, chief equity marketing officer at Tokai Tokyo Securities.

"Exporters and other auto shares are all pretty strong on this."

He added: "The Toyota issue is pretty much worn out as a factor; it's been priced in. This is especially true since some of it may have been a kind of Japan-bashing taken up as a political factor." – Reuters