U.S. safety regulators will investigate potential problems with the engines of more than 700,000 Ford vehicles, according to an Associated Press report.
The probe will affect Ford Escape and Fusion and Mercury Mariner and Milan engines in model years 2009-2011.
The cars' and SUVs' engines have been known to surge or stall and can unexpectedly go into low-power "limp home mode," the report stated, citing the National Highway Safety Transportation Administration.
The vehicles have not been recalled, but the investigation may lead to a recall, The New York Daily News reported.
NHTSA and Ford have received nearly 1,500 complaints about the problem, which has resulted in three crashes and one injury, the AP reported.
The Fusion and Milan have the same engine, as do the Escape and Mariner. Ford ended the Mercury brand in 2010.
Ford told the NHTSA that vehicles made from June 22, 2009 to Oct. 15, 2009 may have faulty circuit boards that control throttles, the AP reported.
Nonprofit safety groups and consumers can petition the NHTSA to investigate vehicle problems, which is what prompted the investigation after the North Carolina Consumers Council requested an investigation last year, the report stated.
The NHTSA received 123 complaints of the cars or SUVs going into to limp mode, where the vehicle's speed is limited to 20 mph. Even though the vehicle can still move in limp mode, many drivers would interpret this as stalling, the report stated. Vehicles usually go into limp mode when computers detect an engine problem, slowing the speed of the car to prevent engine damage, the report stated. The power surges which have been cited by owners experiencing the problem can be attributed to engine revolution fluctuations to prevent the car from fully stalling while in limp mode, the report said, citing the NHTSA.
The agency received 59 complaints of engine stalling in 2010 and 2011 Fusions, with 80 percent of those complaints occurring within the last year, showing an increasing trend, the report stated.
The report also stated Ford has received 27,505 warranty claims in which throttle bodies were repaired or replaced.
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