OEM parts categories for 1991 Audi 100 Quattro: A/C & Heating (A/C & Heater Control Units, A/C Compressor, A/C Condenser, Air Conditioner, Automatic Temperature Controls, Blower Motor & Fan, Heater Core & Control Valve) | Air & Fuel Delivery (Air Inlet, Cruise Control System, Fuel Injection, Fuel Supply, Fuel System Components, Intake Manifold, Intercooler, Throttle Body, Turbocharger) | Belts & Cooling (Belts, Cooling System, Radiator, Water Pump, Cooling Fan, Oil Cooler, Radiator & Components, Radiator Support) | Body & Hardware (Back Glass, Center Pillar & Rocker, Console, Cowl, Door & Components, Fender & Components, Exterior Trim, Front Bumper, Front Door, Front Door - Glass & Hardware, Glass & Hardware - Quarter Panel, Grille & Components, Hood & Components, Inner Components - Quarter Panel, Instrument Panel, Lift Gate, Quarter Panel & Components, Rear Body, Rear Bumper, Rear Door, Rear Door - Glass & Hardware, Rear Floor, Roof & Back Glass, Seats & Track Components, Structural Components & Rails, Sunroof, Tail Gate, Trunk, Trunk Lid, Windshield Glass, Wiper & Washer Components) | Brakes (Anti-Lock Brakes, Brake Components, Front Brakes, Hydraulic System, Parking Brake, Rear Brakes, Traction Control Components) | Charging & Starting (Alternator, Headlamps, Bulbs, Flashers, Ignition System, Ignition Lock, Distributor, Supplemental Restraint System, Antenna & Radio, Battery, Door, Gauges, Heated Seats, Horn, Instruments & Gauges, Powertrain Control, Senders, Sunroof, Switches, Window Defroster, Wipers, Starter) | Driveline & Axles (Front Axle Shafts & Joints, Drive Axles, Rear Axle, Axle Shafts & Joints, Differential, Propeller Shaft) | Electrical (ABS Components, Air Bag Components, Headlamps, Bulbs, Flashers, Ignition System, Ignition Lock, Distributor, Supplemental Restraint System, Antenna & Radio, Battery, Door, Gauges, Heated Seats, Horn, Instruments & Gauges, Powertrain Control, Senders, Sunroof, Switches, Window Defroster, Wipers, Seat Belt) | Emission Control & Exhaust (EGR System, Emission Components, Exhaust Components, Exhaust Manifold) | Engine (Engine & Trans Mounting, Engine Parts, Mounts, Cylinder Head & Valves, Camshaft & Timing, Oil Pan, Oil Pump, Crankshaft & Bearings, Pistons, Rings & Bearings) | Headlights & Lighting (Backup & Tail Lamps, Headlamps, Headlamps, Bulbs, Flashers, Ignition System, Ignition Lock, Distributor, Supplemental Restraint System, Antenna & Radio, Battery, Door, Gauges, Heated Seats, Horn, Instruments & Gauges, Powertrain Control, Senders, Sunroof, Switches, Window Defroster, Wipers, High Mount Lamps, License Lamps, Park Lamps, Rear Lamps, Side Marker Lamps) | Interior & Exterior Trim (Fender & Components, Exterior Trim, Interior Trim) | Maintenance & Lubrication (Automatic Transmission, Filters) | Steering (P/S Pump & Hoses, Steering Gear & Linkage, Power Steering Pump, Steering Column & Wheel, Steering Gear & Linkage) | Suspension (Axle Shaft - Rear, Drive Axles - Front, Front Suspension Components, Lower Control Arm, Stabilizer Bar, Rear Axle, Stabilizer Bar, Suspension Components, Rear Suspension Components, Lower Control Arm, Shocks & Suspension Components - Rear, Wheels, Covers & Trim) | Transmission (Automatic Transmission, Clutch & Flywheel, Hydraulic System)