This Preliminary Information communication provides information to the technician about vehicles that have a loud whine noise from under the hood. On 2010 Buick LaCrosse and 2011 Buick Regal with Regular Production Option Code (LAF) engine technician will need to compare to a known good vehicle and replace the Brake Booster Electric Vacuum Pump only if an abnormal noise is heard. On the 2011 - 2014 Buick LaCrosse and 2012 - 2014 Buick Regal technician will need to compare to a known good vehicle and replace the Brake Booster Electric Vacuum Pump only if an abnormal noise is heard.