Blower Problem

sometimes on vehicles with a 2 wire fan motor the blower can run backward so by reversing the 2 wires it will turn in the right direction and start blowing the full amount of air again. if that is not the problem check for vacuum leaks the doors for the heater are vacuum controlled also your vacuum switch in the dash can be bad, you can usually hear a faint hiss in the vehicle. usually when there is a vacuum problem the heater only blows on defrost.....Hope this helps ....Good Luck