🏷️ Basic Information Identification Make: Audi Model: 100 Year: 1991 Codes Chassis Code: C3-44 👋 Introduction Market Position Positioning: The 1991 Audi 100 represented Audi's upscale offering in the executive sedan segment, competing with established European and American luxury brands. Competitive Analysis Competitors: Competed with vehicles such as the BMW 5 Series, Mercedes-Benz E-Class, and Volvo 240/740. Key Features Aerodynamics: The C3 platform was renowned for its advanced aerodynamics, contributing to fuel efficiency and reduced wind noise. Quattro AWD: Availability of the iconic Quattro all-wheel-drive system, a hallmark of Audi's performance and handling capabilities. Interior Design: Focus on high-quality materials, ergonomic design, and comfortable seating for a premium feel. 📋 Manual Details Coverage Areas Coverage Scope: All models and all repairs A-Z Page Count Estimated Page Count: 800+ Manual Type Type: Service and Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine: Detailed diagnostic, repair, and overhaul procedures for gasoline engines, including fuel injection systems (KE-Jetronic), ignition systems, emissions control, cooling, and lubrication. Transmission: Comprehensive coverage of manual and automatic transmissions, including clutch operation, gear shifting mechanisms, torque converter systems, transmission fluid maintenance, and internal component repair. Brakes: In-depth information on hydraulic brake systems, ABS (Anti-lock Braking System) diagnosis and repair, parking brake systems, brake fluid specifications, and component replacement (master cylinder, calipers, rotors). Suspension Steering: Detailed procedures for front and rear suspension components (struts, shocks, control arms, bushings), steering system diagnosis and repair (power steering pump, rack and pinion), wheel alignment specifications. Electrical Electronics: Extensive coverage of the vehicle's electrical system, including wiring diagrams, battery, starting system, charging system (alternator), lighting, instrumentation, power windows, central locking, and electronic control units (ECUs). Climate Control: Diagnosis and repair of HVAC (Heating, Ventilation, and Air Conditioning) systems, including refrigerant handling, compressor service, blower motor, and climate control panel operations. Body Chassis: Information on body panel repair, door mechanisms, interior trim removal and installation, glass replacement, and chassis component maintenance. Procedures Included Maintenance: Regular service intervals, oil change procedures, filter replacements (oil, air, fuel), spark plug service, coolant flushes, brake inspections, and general preventative maintenance tasks. Diagnostics: Systematic troubleshooting guides, symptom-based diagnostics, fault code interpretation (where applicable), and diagnostic test procedures for all major systems. Repair: Step-by-step instructions for component removal, installation, and overhaul for all major mechanical and electrical systems. Torque Specifications: Detailed torque specifications for all critical fasteners, bolts, and nuts across various vehicle systems. Wiring Diagrams: Comprehensive and detailed electrical wiring diagrams for all vehicle circuits. Technical Depth Depth: Complete factory-level repair and diagnostic information, suitable for professional technicians and advanced DIY enthusiasts. 📊 Manual Specifications File Format File Type: PDF Print Quality Quality: High-resolution, searchable text and clear diagrams for easy navigation and printing. Binding Type Binding: N/A (Digital Download) Paper Type Paper Quality: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Code: Various, common include 2.3L 5-cylinder (NG, NF) Engine Type: Inline 5-cylinder, 20-valve (typically) Displacement: 2309 cc (2.3 Liters) Performance Horsepower: Approximately 130-136 hp @ 5600 rpm (depending on specific engine variant and market) Torque: Approximately 140-145 lb-ft @ 3000-3500 rpm (depending on specific engine variant and market) Fuel System Fuel Injection: Bosch KE-Jetronic CIS-E (Continuous Injection System - Electronic) Fuel Type: Unleaded Gasoline Cooling System Coolant Type: Ethylene Glycol based coolant (e.g., G11 specification) Lubrication Oil Capacity: Approximately 4.5 - 5.0 liters (with filter change, depending on engine variant) Recommended Oil Viscosity: 10W-40 or 15W-40 (refer to manual for specific ambient temperature ranges) 🔧 Transmission Standard Type: 5-speed Manual Transmission Optional Type: 4-speed Automatic Transmission (e.g., ZF 4HP22) Features AWD System: Optional Quattro permanent all-wheel drive system available with both manual and automatic transmissions. Fluid Specifications Auto Atf Type: Dexron III or equivalent (check manual for exact specification) Fluid Specifications Manual Gear Oil Type: API GL-4 SAE 75W-90 or SAE 80W-90 (check manual for specific axle/transmission type) 📐 Dimensions Exterior Length: Approximately 4780 mm (188.2 inches) Width: Approximately 1770 mm (69.7 inches) Height: Approximately 1420 mm (55.9 inches) Wheelbase Wheelbase: Approximately 2687 mm (105.8 inches) Weights Curb Weight: Approximately 1350 - 1550 kg (2976 - 3417 lbs) depending on configuration Gross Vehicle Weight: Varies by model/engine, refer to VIN plate Wheels Tires Wheel Bolt Pattern: 5x112mm Standard Tire Size: Typically 195/65R15 or 205/60R15 (check specific model) 🛡️ Safety Features Ratings Crash Test Data: Limited standardized crash test data from this era compared to modern standards. Audi emphasized safety through its 'Procon-ten' system. Active Features ABS: Optional Anti-lock Braking System (ABS) available on many models. AWD: Quattro all-wheel-drive system offered significant improvements in traction and stability. Passive Features Airbags: Driver's airbag typically optional or standard on higher trims; passenger airbag was less common. Seatbelts: Front and rear seat belts, with front seat belt pretensioners often standard. Procon Ten: Audi's proprietary 'Procon-ten' passive safety system, which tightened seatbelts and moved the...