My AC has always blown hard from the center vents and pretty much nothing from the side vents. They have a trickle of cold air, but no real force. If I close the center vent that forces cold air to the sides. But still very light pressure.
Is there a way I can re-adjust the system to get cold air to flow evenly between the sides and the center vents?

 

Was just about to post the same question. I was wondering if the Doors were half closed or a damper is stuck.