NEW YORK (CNNMoney.com) -- Federal car safety regulators are warning owners of 2010 Ford Fusion and Mercury Milan sedans of possible dangers from floor mats.
Owners were told gas pedals could become stuck if all-weather floor mats are stacked on top of the cars' standard mats.
"Any Ford 'All Weather' optional floor mat should be placed in the driver's side foot well only after first unfastening and removing the standard, carpeted floor mat," the National Highway Transportation Safety Administration said in a statement Friday. "This is the only way to ensure that the 'All Weather' optional floor mat is physically secured to the floor."
Last fall, Toyota (TM) recalled cars because of a similar issue. That recall, which ultimately included about 5 million vehicles, started after a family was killed in a crash that was apparently caused by a gas pedal trapped by an all-weather floor mat.
The auto safety agency has received three complaints that gas pedals on the Ford vehicles got stuck after an all weather floor mat slipped forward and trapped the gas pedal. This usually happens when the gas pedal is pushed all the way to the floor or close to it. None of the complaints have involved crashes, injuries or deaths.
The agency is opening a formal investigation into the problem.
The Ford Fusion and Mercury Milan are two closely related mid-sized cars. A third version, the Lincoln MkZ, wasn't included in the warning, but it was not immediately clear why. It's also unclear whether the warnings and investigation might also apply to earlier model year Fusions and Milans.
"We do not recommend stacking floor mats in any vehicle from any automaker," said Ford Motor Co. spokesman Said Deep.
Ford's all weather floor mats come with multiple clear warnings not to stack the floor mats and to install them properly, Deep said.
"We will cooperate fully with NHTSA, as we always do," he said.
The stuck pedal problem can happen in many vehicles, NHTSA warned. The agency urged owners to use care when installing floor mats and follow manufacturers' instructions.
If a gas pedal becomes stuck during driving, drivers should press firmly on the brake pedal -- do not pump the brakes -- and shift the transmission to neutral then steer the car safely to the side of the road, NHTSA advised.
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