Do you want to sleep peacefully at night without worrying about a stock? Then avoid or sell Toyota (TM) shares.

Toyota has a full-blown crisis on its hands. As has been widely reported, sticking gas pedals caused Toyota to announce a recall last week affecting 2.3 million vehicles in the U.S., including some of its most popular models. And, in a separate recall announced late last year, a floor mat defect that could also cause uncontrolled acceleration led the company to call back models from its high-end Lexus brand, hitherto renowned for quality and reliability, along with other Toyota models. These incidents alone would warrant investor caution. But the problem has been compounded by long-delayed and less-than-reassuring responses from Toyota.

First, consider the problems themselves. Last August, a Lexus ES 350 was weaving wildly and at high speed over 120 miles an hour through traffic on California Highway 125 near San Diego until it struck another car, veered off the road entirely, crashed through a fence, hit a dirt embankment and soared more than 100 feet before crashing. The passengers, off-duty police officer Mark Saylor, 45, his wife, his 13-year-old daughter and his brother-in-law, were killed. Just before the crash, a passenger had dialed 911 and reported that the gas pedal was stuck and the car was out of control, according to news reports.

An isolated incident? Apparently not. There have been hundreds of reports about uncontrolled acceleration in Toyotas, few of which came close to the tragic circumstances of last August. But the problem for Toyota isn t just the frequency of such reports but also the potentially catastrophic consequences. It s one thing to experience an electrical glitch or a problem opening the trunk, which might sink a vehicle in the J.D. Power survey ratings. But as the San Diego incident so vividly demonstrated, a runaway vehicle and a defect jamming the accelerator are terrifying and potentially fatal. As a Toyota driver told the New York Times, every time I get in this vehicle I m afraid of it.

Since the San Diego incident, Toyota has announced two separate recalls affecting 5.3 million vehicles and attributed the problem in the Lexus to a floor mat. In November, the company said in a letter to customers that no defect exists in vehicles in which the driver s floor mat is compatible with the vehicle and properly secured. The National Highway Traffic Safety Administration (NHTSA) immediately denounced Toyota s explanation as inaccurate and misleading, saying the problem was related to accelerator and floor pan design. Toyota apologized, but later that month, a spokesman for Toyota, Irv Miller, told the New York Times that the firm had no indication that the reported acceleration issues had been the result of any problem but the floor mats jamming the gas pedals.

On Tuesday, John Hanson, a Toyota spokesman told me that since the San Diego crash remains under investigation by the sheriff s office, he can t comment on its causes. However, he said that Toyota still believes that floor mat entrapment was the issue.

Public skepticism about Toyota s explanation increased this past month. On Jan. 21, the company issued a separate recall related to the gas pedal mechanism in an additional 2.3 million vehicles. Last week, Toyota said it had written the NHTSA to expand the floor mat recall to include 11 additional models.

Last week, Toyota seemed to be floundering. Under pressure from the NHTSA, Toyota announced it would stop selling eight models. Later that week, a spokesman, Mike Goss, told the Wall Street Journal that the company had solved the mechanical problem, but then declined to say what the fix was. Toyota ads were still touting the company's quality until the end of the week when they were cancelled. On Monday, Toyota finally issued a statement purporting to identify the mechanical problem and promising that dealerships would stay open late to accommodate customers and make needed repairs. Investors seemed relieved pushing Toyota shares up nearly 4%.

But is this the end of the story? Has Toyota finally solved the problem? It will take months before we know. Meanwhile, Congress is going to have hearings as well it should given that the NHTSA has been getting complaints about uncontrolled acceleration in Toyotas since 2004. Why has it taken the company six years to address the problem?

Mr. Hanson, the Toyota spokesman, said that all carmakers experience unintended acceleration problems usually because the driver hits the gas pedal instead of the brake. Toyota only identified the gas pedal problem in October. It both pinpointed the problem and a solution in just 90 days, which is near-record time. He stressed that the floor mat problem is separate and unrelated. Nonetheless: We re very disappointed with what s happening now and we re sorry to our owners and the public, he says. Now our job is to do everything we can to get our owners back into their cars and assure them they are driving safe vehicles."

This strikes me as more than a mechanical issue albeit one potentially affecting millions of vehicles. Toyota s credibility is also on the line. The damage to Toyota s reputation is incalculable. The damage to its brands isn t: that s apparent in the January sales figures Toyota released today.

Toyota shares were over $90 as recently as Jan. 19. They closed Monday at just over $80, which strikes me as a modest decline under the circumstances. If I owned shares, I d seize the chance to get out. Toyota has a vast infrastructure and a long history of quality and innovation. But its floor mat and gas pedal nightmares are likely just beginning.