Hi Guys is there a way to close the centre air vents the way the side ones have a wheel to close them. The aircon blower on this car is very weak. Part of the issue is that the rear passenger air vent robs the blower of some power even when closed due to it not shutting of airtight. If the left central air vent could be closed then it would help blow out more air from the ones that are open. Has anyone done an upgrade of the blower motor?