Selector Lever Linkage Check
WARNING: This page is about a different car, the 2012 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
Hydraulic leakage at the manual control valve can cause delay in engagements and/or slipping while operating if the linkage is not correctly adjusted. Refer to AUTOMATIC TRANSAXLE EXTERNAL CONTROLS - AISIN AW21/6F35 for selector lever linkage adjustment.