NHTSA closes probe into Ford engine failures, AP reports

The U.S. National Highway Traffic Safety Administration has closed a two and a half year probe into Ford (F) engine failures after the car maker replaced engines or extended the warranty on certain vehicles, the Associated Press reports. The auto safety regulator said that its analysis traced the issue to intake valves that can fracture inside some 2.7-liter and 3-liter turbocharged engines, the report says.