The Prius was not part of the most recent recall, but Japan's transport ministry ordered the company to investigate complaints of brake problems with the hybrid. LaHood said his department, too, was looking into brake problems. About 100 complaints over Prius brakes have been filed in the U.S. and Japan.
Harried dealers began receiving parts to repair defective gas pedals in millions of vehicles and said they'd be extending their hours deep into the night to try and catch up. Toyota said that would solve the problem - which it said was extremely rare - of cars unaccountably accelerating.
At a congressional hearing, LaHood said his advice to an owner of a recalled Toyota would be to "stop driving it. Take it to a Toyota dealer because they believe they have a fix for it." His comments prompted new questions and rattled Toyota stockholders, causing shares to plunge 8 percent before they recovered, declining 6 percent for the day.
LaHood later told reporters, "What I said in there was obviously a misstatement. What I meant to say ... was if you own one of these cars or if you're in doubt, take it to the dealer and they're going to fix it."
Adding to Toyota's woes, LaHood said his department had received new complaints about electronics and would undertake a broad review, looking beyond Toyota vehicles, into whether automobile engines could be disrupted by electromagnetic interference caused by power lines or other sources. Toyota has said it investigated for electronic problems and failed to find a single case pointing that direction.
Toyota Motor Corp., in a statement, said if owners were experiencing problems with the accelerator pedal "please contact your dealer without delay. If you are not experiencing any issues with your pedal, we are confident that your vehicle is safe to drive."
But the damage was done for many drivers.
Meredyth Waterman, who bought a 2010 Toyota Corolla in December, said the alarming statements from Washington confused her and she planned to wait until her dealer told her to come get the fix to bring her car in for repairs.
"If it is largely believed to be a rare instance, why would he tell people to stop driving their cars?" asked Waterman, of Burrillville, R.I. "It was an irresponsible thing to say."
The confusion came as the world's No. 1 automaker dealt with fresh probes in the U.S. and Japan over the Prius, the best-selling gas-electric hybrid, and growing interest from congressional and other government investigators. Toyota has shut down several new vehicle assembly lines and is rushing parts to dealers to fix problems with the accelerators, trying to preserve a reputation of building safe, durable vehicles.
Since October, Toyota first recalled about 5 million vehicles over problems with floor mats trapping gas pedals and now, in a recall announced Jan. 21, some 2.3 million vehicles amid concerns that gas pedals could become stuck or slow to return to the idle position. The latest recall involves 2009-10 RAV4 crossovers, 2009-10 Corollas, 2009-10 Matrix hatchbacks, 2005-10 Avalons, 2007-10 Camrys, 2010 Highlander crossovers, 2007-10 Tundra pickups and 2008-10 Sequoia SUVs.
Lawmakers who are now digging into the recalls said they would also look into the Prius. Rep. Bart Stupak, chairman of the House Energy and Commerce investigative subcommittee, said his panel would request a briefing from Toyota officials about the hybrid.
New York Rep. Edolphus Towns, chairman of the House Oversight and Government Reform Committee, sought more information about the acceleration issue from Yoshi Inaba, chairman and CEO of Toyota Motor North America and asked the question on the minds of Toyota owners: "Is it safe to drive the Toyota models that have been recalled?"
Towns' committee, which is planning a Feb. 10 hearing, also wants more details on how Toyota handled complaints about pedal entrapment, reports of stuck accelerators and electrical problems. Other panels in the House and Senate also are planning hearings.
Many consumer groups have questioned whether Toyota's fix will work and have asserted it could be connected to problems with the electronic throttle control systems.
Joan Claybrook, who formerly lead Public Citizen, a watchdog group, noted that Toyota told owners during last year's recall to remove floor mats to keep the accelerator pedal from becoming jammed. "I don't think that's what the issue is. I think it has to be electronic when it slam dunks and takes off and goes 120 miles an hour," Claybrook said.
LaHood, who plans to speak with Toyota President Akio Toyoda about the recalls, said the government is considering civil penalties against the carmaker. But he also said that it appeared "Toyota is making an all-out effort to do all that they can to fix these cars."
The Obama administration has been forced to backtrack on several statements during its first year, though LaHood's warning was particularly striking.
Last year, when LaHood suggested the administration consider taxing motorists based on how many miles they drive instead of how much gasoline they buy, his comments were quickly rejected by the White House. Vice President Joe Biden triggered a day of backtracking after publicly swearing off trains and planes because of swine flu worries.
LaHood's comments irked many dealers, who have been fielding calls from nervous customers for days. Most dealers are just getting the parts, a steel shim a couple of millimeters thick, to be inserted in the pedal assembly to address potential friction that could cause the pedal to stick.
The secretary "has the best of intentions, but unfortunately we can't fix 100 cars at the same time," said Adam Lee, head of Lee Auto Malls and owner of a Toyota dealership in Topsham, Maine.
"I'm sure he has the best of intentions but it may not be very constructive for us."
Earl Stewart, who owns a Toyota dealership in North Palm Beach, Fla., said LaHood's comments "could instill panic." Stewart was expecting to begin making repairs - at half an hour per vehicle - later Wednesday.
"We're leaving our service department open 'til the last customer tonight," he said. "After Ray LaHood's statement, it might be all night."