On the BMW E30 3 Series, There is a small resistor pack that can sometimes fail. The resulting condition usually results in a situation where the fan only operates in the full on position. If this has happened, these new resistors are the fix.
64-11-1-370-927-BOE
Blower Resistor for Automatic Heater Regulator, 318i (through 8/84), 325e/es (through 8/84) Brand: Genuine BMW [More Info]
Blower Motor Assembly, for Heater System (NOTE: Only for cars with aluminum heater core), 318i/is/iC (1991), 325/e/es/i/is/iC/iX (1984-91), M3 (1987-91) Brand: Genuine BMW [More Info]
$479.75
64-11-1-370-930-M6
Blower Motor Assembly, for Heater System (NOTE: Only for cars with aluminum heater core), BMW E30 3 Series, All (1984-5/89) Brand: Behr [More Info]
$266.00
64-11-1-466-015-BOE
A/C Blower Motor Plastic Heater Inlets, BMW E30 3 Series, All (1984-5/89) Brand: Genuine BMW [More Info]
No Longer Available
A/C Service Valve
64-50-9-177-579-M325
A/C Service Valve for Suction Pipe (R134A), Each Brand: Santech [More Info]
$9.00
Einszett A/C Odor & Bacteria Remover
Don't mask odors with fragrances -- treat them. Klima-Cleaner is an effective means for removing odors from the air conditioning unit by eliminating odor-causing bacteria, fungi and other germs. Works by effectively cleaning the evaporator -- the source of the problem. Simply insert included spray hose into the center air vents in your vehicle's interior and spray. Allow to work for 30 minutes. Creates a healthy and fresh smelling environment that lasts for months. 250 ml aerosol *Ground Shipping Only CAUTION: Recommended for professional application only. On certain vehicle makes, damage may occur if product is not applied properly. If uncertain about application, have a certified mechanic apply product.