🏷️ Basic Information Identification Make: Buick Model: Century Year: 1991 Codes Platform: GM W-body 👋 Introduction Market Position Positioning: The 1991 Buick Century was a popular mid-size sedan and coupe in the American market, positioned as a comfortable and reliable family car with a focus on value and practicality. Competitive Analysis Competitors: Competed against vehicles like the Ford Taurus, Chevrolet Lumina, Dodge Spirit, and Honda Accord. Key Features Features: Known for its comfortable ride, spacious interior, and a range of available engine options. The W-body platform provided a solid foundation for handling and passenger comfort. Ui Design: User-friendly interface for easy navigation and information retrieval, designed for both novice and experienced mechanics. 📋 Manual Details Coverage Areas Primary Coverage: Service and Repair Secondary Coverage: Maintenance, Diagnostics, Troubleshooting Page Count Estimated Pages: Varies by engine and options (typically 1000+ pages for full factory manual equivalent) Manual Type Type: Service and Repair Manual Software Source: Licensed information derived from Original Equipment (OE) manufacturer materials. Language Language: English Format Format: PDF Download (Digital Access) 📖 Manual Coverage Systems Covered Engine: All gasoline engines, including components like ignition, fuel, cooling, lubrication, and emission control systems. Transmission: Automatic transmission service, overhaul, and diagnosis. Brakes: Hydraulic brake systems (front disc, rear drum), parking brake, ABS (if equipped). Steering: Power steering system, steering column, and linkages. Suspension: Front and rear suspension components, alignment specifications. Electrical: 12-volt electrical system, battery, charging system, starting system, lighting, instrument panel, power accessories, wiring diagrams. HVAC: Heating, Ventilation, and Air Conditioning (HVAC) system service and repair. Body: Body and chassis repair, interior and exterior trim, doors, glass, and weatherstripping. Fuel System: Fuel pump, fuel filter, fuel injectors, fuel pressure regulator, and fuel tank service. Cooling System: Radiator, water pump, thermostat, hoses, and heater core replacement and service. Procedures Included Maintenance: Scheduled maintenance, oil changes, fluid checks and changes, filter replacements, spark plug replacement, belt inspection and replacement. Repair: Detailed step-by-step repair procedures for all major vehicle systems, including component removal, installation, and adjustment. Diagnostics: Troubleshooting guides and diagnostic charts for common and uncommon issues, diagnostic trouble codes (DTCs) for OBD-I systems. Specifications: Torque specifications, clearances, fluid capacities, diagnostic parameters, and alignment data. Timing Belt Or Chain: Procedures for timing belt replacement (if applicable to specific engine) or timing chain inspection and replacement. Exhaust System: Diagnosis and repair of exhaust leaks, muffler and catalytic converter replacement. Air Conditioning Service: Refrigerant handling, component replacement (compressor, condenser, evaporator), leak detection, and evacuation/recharging. Technical Depth Depth: Comprehensive, factory-derived information suitable for professional technicians and advanced DIY enthusiasts. Covers everything from basic tune-ups to complete engine and transmission overhauls. Engine Rebuild: Includes detailed instructions for engine disassembly, inspection, cleaning, machining, and reassembly, with precise tolerances and specifications. Electrical Diagnostics: Extensive use of wiring diagrams, component testing procedures, and diagnostic flowcharts for pinpointing electrical faults. 📊 Manual Specifications File Format Quality: High-resolution, searchable PDF with clear diagrams and illustrations. Searchability: Fully searchable text for quick access to specific topics and procedures. Print Quality Printable: Printable pages for easy workshop use. Binding Type Binding: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Option 1: 2.5L L4 (Iron Duke), 110 HP @ 4800 RPM, 145 lb-ft @ 2400 RPM Engine Option 2: 3.3L V6 (3300), 160 HP @ 4800 RPM, 185 lb-ft @ 3200 RPM Engine Option 3: 3.1L V6 (3100), 140 HP @ 4800 RPM, 170 lb-ft @ 3200 RPM Performance Horsepower Range: 110-160 HP Torque Range: 145-185 lb-ft Fuel System Fuel Delivery: Port Fuel Injection (PFI) Ignition System: Distributorless Ignition System (DIS) or Distributor Ignition System (DIS) depending on engine variant. Engine Option 1 Engine Code L4: 2.5L Tech IV (LL8) Engine Option 2 Engine Code V6 3300: 3.3L 3300 (LG7) Engine Option 3 Engine Code V6 3100: 3.1L 3100 (LHO) 🔧 Transmission Standard Transmission Option 1: 3-speed Automatic (THM3T40) Optional Transmission Option 2: 4-speed Automatic (4T60-E) Features Lock-Up Torque Converter: Present on automatic transmissions for improved fuel efficiency. 📐 Dimensions Exterior Wheelbase: 107.0 inches Length: 191.5 inches Width: 68.3 inches Height: 54.2 inches Weights Curb Weight Approx: 3000-3300 lbs (depending on engine and trim) 🛡️ Safety Features Ratings NHTSA Frontal Impact Driver: Not explicitly rated for this year by modern standards, but early W-body designs were considered safe for their era. Active Features ABS: Optional Anti-lock Braking System (ABS) on some models. Passive Features Airbags: Driver-side airbag standard on most models for 1991. Seatbelts: Front 3-point seatbelts, rear lap and shoulder belts. 💡 Technology Features Infotainment Audio System: AM/FM stereo radio, optional cassette player, optional CD player. Basic speaker configurations. Driver Assistance Cruise Control: Optional on most models. Connectivity Connectivity Features: None by modern standards; primarily mechanical and basic electrical systems. 🔧 Maintenance Service Intervals Oil Change: Every 3,000-5,000 miles or 3-6 months (depending on oil type and driving...