2000 Mercury Marquis blower motor

My 2000 mercury grand marquis has started having blower motor issues. When it is turned on, the blower runs high then low then high, it acts like there is a loose wire or something. When it is blowing, it tends to only blow high but it goes on and off constantly. This is a new issue, I have had the car for about a year and it has run great until just recently. It really acts like a loose connection or wire, but I have no idea where to start looking. Help!