ORLANDO, Fla. -

The National Highway Traffic Safety Administration has announced a probe into the Ford Taurus and Mercury Sable for possible throttle dysfunction.  The investigation affects an estimated 310,000 cars from model years 2000-2003 only.

NHSTA says the speed control collar attachment may fracture and result in a stuck throttle.  The agency has not announced a recall yet, pending the conclusion of its investigation.

The government has received 50 complaints about sticky throttles in Taurus and Sable vehicles equipped with four-valve, three-liter V6 Duractec engines.  No crashes or injuries have been reported.

According to NHTSA, the throttle failure mode is not a problem in models with a different size engine or models from 2004-2007.

The Ford Taurus and Mercury Sable were built to be nearly identical cars. Ford suspended the Mercury brand two years ago.