the up and down blower speed could be the brushes on the motor, i have read that some people found replacement brushes at the vacuum cleaner repair shop, just a thought........
Gretchen 1981 240D 4-spd 213,000 mi
1979 240D 4-spd 298,000 mi parts car
1994 BMW 325is
1991 Dodge turbo diesel
1997 ford expedition