Washington-Toyota Motor Corporation is facing more questions from the US Congress over its troubled safety record as top company officials appear at a Senate hearing on the automaker's huge worldwide recall of 8.5 million vehicles. The Senate Committee on Commerce, Science and Transportation will hold the third congressional hearing in seven days on whether Toyota and US safety regulators acted swiftly enough to deal with cases of sudden unintended acceleration of the Japanese automaker's cars and trucks. Three Toyota executives and Transportation Secretary Ray LaHood are among the witnesses expected on Tuesday. Toyota President Akio Toyoda pledged last week before the House Oversight Committee to be more responsive to driver complaints and safety warnings from the government.