2003 Pontiac Grand Am Air vent problem

I had a problem with my blower only working at the top speed but even then would not blow out very hard. I replaced the resistor that goes to the blower motor and
know blows well to the foot position but still blows sparingly to the the top position. I'm wondering if I could have hit something when I was changing the resistor or is there something else that could be needing some repair. Thanks in advance for the advice. Leroy