This manual covers the Buick Century, produced from 1997 to 2005, a vehicle renowned for its comfort-oriented design and spacious interior, built on the versatile W-body platform. Available as a 4-door sedan or 4-door coupe, the 2003 Buick Century offered a choice of efficient powertrains, including the 2.2L Ecotec I4 and the robust 3.1L or 3.8L GM V6 engines. This generation of the Century lineage emphasizes a smooth ride and a focus on value, embodying Buick's heritage of comfortable and reliable transportation. This comprehensive Factory Service Manual provides in-depth guidance for the service, maintenance, diagnosis, and repair of the 2003 Buick Century. It covers all major systems, including engine mechanicals, fuel and ignition systems, drivetrain, suspension, brakes, and electrical components. Detailed procedures for maintenance tasks, diagnostic troubleshooting, and component repair are included, offering essential information for DIY owners, independent repair shops, and professional technicians. The manual's extensive coverage ensures that users have access to authoritative, vehicle-specific data to keep their Buick Century operating optimally. 🏷️ Basic Information Identification Make: Buick Model: Century Year: 2003 Codes Platform Code: W-body 👋 Introduction Market Position Target Audience: DIY car owners, independent repair shops, auto technicians seeking dealership-level repair data. Competitive Analysis Advantage: Provides the same authoritative information used by certified dealership technicians, offering vehicle-specific, not generic, repair data. PDF format offers flexibility for printing and digital access. Key Features Format Advantage: Searchable text, ability to print specific pages, zoomable illustrations and schematics, eliminates physical wear and tear of traditional manuals. 📋 Manual Details Coverage Areas Primary Coverage: Service, Maintenance, Diagnosis, and Repair Page Count Estimated Page Count: Thousands (as a comprehensive PDF) Manual Type Type: Factory Service Manual / Repair Manual Language Language: English Format Format: PDF Download 📖 Manual Coverage Systems Covered Engine Mechanical: Engine assembly, cylinder head, valve train, pistons, crankshaft, connecting rods, engine block, timing system, lubrication, cooling system. Engine Control System: Fuel injection, ignition system, engine control module (ECM), sensors (MAP, TPS, O2, Crankshaft Position, Camshaft Position), actuators, emissions controls. Fuel System: Fuel tank, fuel pump, fuel filter, fuel lines, fuel injectors, fuel pressure regulator, evaporative emission control (EVAP). Intake Exhaust Cooling: Intake manifold, throttle body, exhaust manifold, catalytic converter, muffler, radiator, cooling fan, water pump, thermostat. Lubrication: Oil pan, oil pump, oil filter, oil galleries, lubrication specifications. Ignition Starting Charging: Spark plugs, ignition coils, battery, starter motor, alternator, voltage regulator, wiring. Automatic Transmission: Transmission assembly, torque converter, valve body, clutch packs, gear sets, hydraulic system, transmission control module (TCM), fluid specifications, service procedures. Manual Transmission: Transmission assembly, clutch assembly, gear shift mechanism, fluid specifications, service procedures (if applicable to specific trims/engines). Drivetrain: Transfer case (if applicable), propeller shaft, drive shafts, constant velocity (CV) joints, differential, axle shafts, wheel bearings. Suspension: Front suspension (struts, control arms, ball joints, sway bar), rear suspension (shocks, springs, control arms, trailing arms, sway bar), alignment specifications. Steering: Steering column, steering gear/rack and pinion, power steering pump, power steering fluid, steering linkage. Brakes: Front brakes (discs, calipers, pads), rear brakes (drums or discs, calipers, pads/shoes), parking brake system, hydraulic lines, brake fluid, ABS system. Wheels Tires: Wheel specifications, tire pressure recommendations, tire rotation, wheel balancing. Body Exterior: Doors, hood, trunk lid, fenders, bumpers, body panels, glass, mirrors, exterior trim, latches, hinges. Body Interior: Seats, dashboard, instrument panel, door panels, headliner, carpeting, interior trim, seat belts, airbags (Supplemental Restraint System - SRS). Electrical Power Distribution: Battery, alternator, fuses, fusible links, relays, wiring harnesses, grounds. Lighting: Headlights, taillights, interior lights, fog lights, bulb types and replacement. Instrumentation Gauges: Instrument cluster, speed sensor, tachometer, fuel gauge, temperature gauge, warning lights, diagnostics. Audio Visual: Radio, speakers, antenna, wiring, installation and removal of components. Climate Control: Air conditioning system (compressor, condenser, evaporator, refrigerant), heater, blower motor, HVAC controls, cabin air filter. Safety Restraint System: Airbag modules, SRS control module, seat belt pre-tensioners, diagnostic procedures for SRS. Cruise Control: Cruise control module, actuators, switches, wiring, diagnostic procedures. Wiper Washer: Wiper motor, wiper arms, wiper blades, washer pump, washer fluid reservoir, nozzles, switches, wiring. Door Locks Security: Power door locks, central locking system, keyless entry, remote key fob, door lock actuators, wiring, alarm system, engine immobilizer. Multiplex Can Communication: Vehicle communication networks (e.g., CAN bus), module communication, diagnostic trouble codes (DTCs) related to network issues. Procedures Included Maintenance Procedures: Oil changes, filter replacements, fluid checks and top-offs, spark plug replacement, belt inspection and replacement, battery testing. Diagnostic Procedures: Troubleshooting guides, symptom-based diagnostics, diagnostic trouble code (DTC) interpretation and clearing, wiring diagram analysis. Repair Procedures: Component removal and installation, rebuild procedures (e.g., engine, transmission), adjustments, calibration. Electrical Troubleshooting: Wiring schematic interpretation, continuity testing, voltage testing, component testing, circuit diagnosis. Mechanical Adjustments: Brake adjustment, clutch adjustment, parking brake adjustment, door/hood/trunk alignment. Technical Depth Depth: Comprehensive, from basic maintenance to complete engine and transmission overhauls, including advanced diagnostics and electrical system troubleshooting. 📊 Manual...