🏷️ Basic Information Identification Make: Audi Model: A6 Year: 1990 Chassis Code: C4-4A Codes Platform Code: Typ 4A 👋 Introduction Market Position Segment: Executive/Luxury Sedan Positioning: Premium German sedan offering advanced technology and build quality Competitive Analysis Competitors: BMW 5 Series (E34), Mercedes-Benz E-Class (W124), Lexus LS 400 (UCF10) Key Features Design Philosophy: Understated elegance, aerodynamic efficiency, driver-focused cockpit Engineering Focus: Solid construction, quattro all-wheel drive option, refined powertrains 📋 Manual Details Coverage Areas Coverage: All models and all repairs A-Z Page Count Page Count: Estimated 1000+ Manual Type Type: Service and Repair Manual Language Language: English Format Format: Digital (PDF) 📖 Manual Coverage Systems Covered Engine Systems: Engine mechanical, fuel injection, ignition, cooling, lubrication, emissions control Transmission Systems: Manual and automatic transmission overhaul, shifting mechanisms, clutch, torque converter Drivetrain Systems: Front-wheel drive, quattro all-wheel drive systems, differentials, driveshafts, CV joints Suspension Steering: Front and rear suspension components, power steering, steering rack, wheel alignment Brake Systems: Disc brakes (front and rear), ABS (Anti-lock Braking System), hydraulic systems, parking brake Electrical Systems: Battery, alternator, starter, lighting, instrumentation, fuses, relays, wiring diagrams Body Chassis: Body panels, doors, windows, bumpers, frame, structural components HVAC Systems: Heating, ventilation, and air conditioning (HVAC) system diagnosis and repair Interior Features: Seats, upholstery, trim, dashboard components, safety belts Procedures Included Maintenance Procedures: Oil changes, filter replacements, spark plug service, coolant flushes, belt adjustments Troubleshooting Guides: Diagnostic flowcharts, symptom-based troubleshooting for common issues Repair Procedures: Component removal and installation, overhaul procedures for major assemblies Diagnostic Procedures: Fault code reading (OBD-I), sensor testing, actuator testing Electrical Repair: Wiring harness repair, component testing and replacement, circuit diagnostics Technical Depth Depth: Comprehensive: From basic maintenance to complete engine and transmission rebuilds Detail Level: Vehicle-specific diagrams, torque specifications, clearances, and procedures 📊 Manual Specifications File Format File Type: PDF Searchability: Fully searchable text content Print Quality Printability: Printable for workshop use Binding Type Binding: N/A (Digital) Paper Type Paper Quality: N/A (Digital) ⚙️ Engine Specifications Primary Engine Engine Code Examples: AAN (2.2L Turbo I5), ABK (2.0L I4), ACK (2.8L V6) Displacement Examples: 2.0L, 2.2L, 2.8L Configuration Examples: Inline-4, Inline-5 (Turbocharged), V6 Performance Horsepower Range: Approx. 113 hp to 230 hp (depending on engine) Torque Range: Approx. 170 Nm to 350 Nm (depending on engine) Fuel System Injection Type: Bosch Motronic electronic fuel injection (EFI) Fuel Type: Unleaded gasoline (Premium recommended) Other Engine Features Timing Drive: Timing belt (Inline-5, V6) or timing chain (some Inline-4 variants) 🔧 Transmission Standard Standard Transmission: 5-speed Manual Transmission Optional Optional Transmission: 4-speed Automatic Transmission (Tiptronic on some later models) Features Drive Layout: Front-wheel drive (FWD) or quattro all-wheel drive (AWD) Automatic Transmission Details: ZF 4HP22 or similar, with torque converter and hydraulic control Manual Transmission Details: Single dry-plate clutch, robust gearbox design 📐 Dimensions Exterior Body Styles: 4-door Sedan (Saloon), 5-door Avant (Wagon) Length: Approx. 4790 mm (Sedan) Width: Approx. 1780 mm Height: Approx. 1420 mm (Sedan) Weights Curb Weight Range: Approx. 1450 kg - 1700 kg (depending on configuration) 🛡️ Safety Features Ratings Crash Test Data: Limited standardized crash test data available for this era, but known for robust body structure Active Features ABS: Available (Bosch Anti-lock Braking System) Passive Features Airbags: Driver's side airbag available on later models/trims Seat Belts: 3-point inertia-reel seatbelts front and rear Body Construction: Integrated safety cage, crumple zones 💡 Technology Features Infotainment Audio System: Factory AM/FM cassette player, optional CD player, speaker options vary by trim Climate Control: Manual or automatic climate control (optional) Driver Assistance Cruise Control: Standard on most models Traction Control: Available on quattro models (ASR - Anti-Slip Regulation) Connectivity Cellular Integration: N/A (No integrated cellular technology for this era) Lighting Headlights: Halogen headlights, potentially with integrated fog lamps 🔧 Maintenance Service Intervals Oil Change Interval: Typically 10,000-15,000 km or 12 months (check owner's manual for specific engine) Timing Belt Replacement: Crucial for Inline-5 and V6 engines; typically every 90,000-120,000 km or 5-7 years (refer to manual) Fluid Specifications Engine Oil Type: API SG or SH, SAE 5W-40, 10W-40, or 15W-40 (depending on climate and engine) Coolant Type: G11 (VW TL 774-C) ethylene glycol based antifreeze Brake Fluid Type: DOT 3 or DOT 4 Automatic Transmission Fluid: G 052 162 A1 or equivalent (e.g., Dexron III) Known Issues Common Engine Issues: Oil leaks (valve cover gasket, oil pan), coolant flange leaks, spark plug blowouts (older engines), timing belt failure if not replaced. Common Transmission Issues: Automatic transmission 'clunk' on shifting, potential valve body issues, manual clutch wear. Common Electrical Issues: Window regulator failures, door lock actuators, dashboard warning light issues, sensor failures (e.g., MAF, ABS). Common Suspension Issues: Worn ball joints, control arm bushings, front strut mounts. 📚 Vehicle History Brand Heritage Brand Focus: German engineering, quattro all-wheel drive technology, luxury and performance Model Evolution Predecessor: Audi 100 (Type 44) Generation Name: C4 (Typ 4A) Transition To...