Toyota's decision to temporarily pull the 2010 model year Lexus GX 460 SUV from dealership showrooms also came after federal safety regulators responded to the magazine's findings by warning drivers to take extra caution when operating the vehicle. Consumer Reports had put the SUV on its "do not buy" list because of a potential rollover risk.
"We are taking the situation with the GX 460 very seriously and are determined to identify and correct the issue Consumer Reports identified," said Mark Templin, Lexus group vice president. "At this time we have asked our dealers to temporarily suspend sales."
He said that Toyota was confident that the GX meets "our high safety standards" and that the automaker's engineering teams were testing the GX using Consumer Reports' parameters to see whether they could also detect the problem.
The sales suspension threatens to further tarnish Toyota -- and especially its luxury brand, which analysts said has largely escaped the image damage that the automaker suffered through its sudden-acceleration-related recalls.
Customers who own the vehicle have the option of taking it back to the dealership for a loaner car, he said.
The National Highway Traffic Safety Administration said it would review the findings of the magazine's test drivers, who said the vehicle failed a key emergency-handling test.
The government on Tuesday advised drivers of the vehicle "to use care and caution. Drivers of all vehicles should avoid excessive speed and aggressive maneuvering in order to maintain control of their vehicles," said Julia Piscitelli, a spokeswoman for a division of the Transportation Department.
The last time Consumer Reports -- famous for its independent testing of autos and buyer recommendations -- issued a do-not-buy warning was in 2001, when the Yonkers, N.Y., magazine said the performance of a Mitsubishi Montero Limited was "not acceptable."
The warnings come as Toyota is using aggressive financing and lease incentives to regain consumer confidence after a series of large recalls and federal probes into safety defects. The Japanese carmaker has issued nearly 10 million recall notices worldwide in recent months for problems related to sudden acceleration that it blames on sticky gas pedals and faulty floor-mat design as well as braking problems in some hybrid models.
Last week the Transportation Department said it would seek the maximum civil fine of $16.4 million against Toyota for delays in notifying authorities about defects in its gas pedals.
"The timing is absolutely terrible for Toyota in terms of trying to rebuild their image," said Rebecca Lindland, auto industry analyst at IHS Global Insight.
She said it was "startling" to see such a harsh move from Consumer Reports, which for years had regarded Toyota products favorably.
Consumer Reports said its testing staff found that "when pushed to its limits on a handling course" on the magazine's test track, the rear of the Lexus GX "slid out until the vehicle was almost sideways" before the vehicle's electronic stability-control system was able to regain control. All four of the magazine's test drivers experienced the problem.
The magazine said that such a situation could happen in "real-world driving" and that it could lead to a rollover accident.
The phenomenon, known as "lift-off oversteer," could occur "when a driver enters a highway's exit ramp or drives through a sweeping turn and encounters an unexpected obstacle or suddenly finds that the turn is too tight for the vehicle's speed," Consumer Reports said.
"A natural impulse is to quickly lift off the accelerator pedal. If that were to happen in the GX, the rear could slide around far enough that a wheel could strike a curb or slide off the pavement," the magazine said.
NHTSA said it would test the SUV to make sure that "it complies with NHTSA's safety standard for electronic stability control and to understand better the results obtained" by Consumers Reports, Piscitelli said.
The electronic stability-control system "should prevent the kind of fishtail event described" in the magazine's tests, she said.
Consumer Reports, which tested a Lexus that it had purchased to review, said no other SUV it had tested in recent years slid out as far as the GX 460. It found the same problems in a second vehicle it obtained to double-check its findings. The Lexus has a $51,970 sticker price.
The magazine's test drivers also tested the Toyota 4Runner. Although it shares the same platform as the GX, it did not display the same problem.
The GX 460 has been on the market for about three months and about 5,000 vehicles have been sold, according to Consumer Reports.
The magazine said it was not aware of any injuries or accidents resulting from the alleged flaw.
Generally, Toyota vehicles have performed well in Consumer Reports tests. A year ago, Consumer Reports recommended 22 of the 25 Toyota products it tested.
But because of the recalls, the magazine recommended only 13 of 26 Toyota models this year.