Neither heater or ac will blow air out unless i bang on the blower fan will come on sometimes

What is your question?

Neither my ac or heater will blow air out the vents but sometimes when I bang on the blower fan motor the air starts blowing. Sometimes for about 10-15 miles and sometimes for inly 2-3 miles. Then it quits blowing and have to bang again.

What makes this problem better or worse?

Going over a bump in road

How long has your 1996 Buick Regal had this problem?

A year