What are you shooting at 1.4? Your DOF is going to be so narrow everything IS going to look blurry. Most fast lenses don't live up to peoples expectations when opened all the way, stop it down and your AF will speed up because now it has something to lock onto. Also learn how to shoot manually before relying on AF. I have maybe one or two AF cameras that rarely if ever get used because I like to shoot manual. When I am out and about I have my lens set for light and distance. I know the effective range of my lens and I do not shoot past that. Seven feet is about the farthest out I shoot because I shoot from the hip and I have learned to judge distance well enough to be able to get the shot.

Stop the lens down and try again.