🏷️ Basic Information Identification Make: Audi Model: A4 Year: 2001 Generation Platform Code: B5 (post-facelift) Codes Chassis Code: 8D2 (Sedan), 8D5 (Avant) 👋 Introduction Market Position Segment: Compact Executive Sedan/Wagon Competitive Analysis Competitors 2001: BMW 3 Series (E46), Mercedes-Benz C-Class (W203), Lexus IS300, Acura TL Key Features Design: Refined styling, Quattro all-wheel-drive option, solid build quality. Powertrain Options: Choice of efficient and powerful 4-cylinder and V6 engines. 📋 Manual Details Coverage Areas Primary Regions: North America, Europe Languages: English Page Count Estimated Pages: 2000+ Manual Type Type: Electrical Service Manual / Wiring Diagrams Format File Format: PDF 📖 Manual Coverage Systems Covered Electrical Systems: All vehicle electrical systems including lighting, power accessories, engine control, ABS, airbags, climate control, audio, instrument cluster, etc. Procedures Included Troubleshooting And Diagnostics: Detailed diagnostic procedures, fault finding charts, symptom-based troubleshooting, wiring harness testing. Component Replacement: Procedures for replacing electrical components and modules. Wiring Diagrams: Comprehensive, high-resolution wiring diagrams with component locations and pinouts. Technical Depth Depth: Advanced diagnostics, electrical component testing, module coding/initialization, circuit tracing. 📊 Manual Specifications File Format PDF Quality: High-resolution scans, searchable text (OCR'd where applicable), zoomable images. Print Quality Recommendation: Suitable for digital viewing or printing; recommended to use Adobe PDF Reader for optimal display of graphics. Binding Type Binding: N/A (Digital Format) Paper Type Paper Type: N/A (Digital Format) ⚙️ Engine Specifications Primary Engine 1 Engine Code: APU/AGN/AVV Engine Type: 1.8L Inline-4 20V Turbocharged (1.8T) Displacement: 1781 cc (1.8 Liters) Horsepower: 150 hp @ 5700 rpm Torque: 155 lb-ft @ 1750 rpm Primary Engine 2 Engine Code: ALT Engine Type: 2.0L Inline-4 (Naturally Aspirated) Displacement: 1984 cc (2.0 Liters) Horsepower: 130 hp @ 5700 rpm Torque: 133 lb-ft @ 3200 rpm Primary Engine 3 Engine Code: AWM Engine Type: 1.8L Inline-4 20V Turbocharged (1.8T) - High Output Displacement: 1781 cc (1.8 Liters) Horsepower: 170 hp @ 5900 rpm Torque: 164 lb-ft @ 1950 rpm Primary Engine 4 Engine Code: AEB/APU/AHA/AMB Engine Type: 2.8L V6 30V (Naturally Aspirated) Displacement: 2771 cc (2.8 Liters) Horsepower: 190 hp @ 6000 rpm Torque: 207 lb-ft @ 3200 rpm Fuel System Injection Type: Electronic Fuel Injection (EFI) with Port Injection Recommended Fuel: Premium Unleaded Gasoline (91 Octane or higher recommended for 1.8T and 2.8 V6) 🔧 Transmission Standard Transmission Type: 5-Speed Manual (FWD) Optional Transmission 1 Type: 5-Speed Tiptronic Automatic (FWD/Quattro) Optional Transmission 2 Type: 6-Speed Manual (Quattro Models) Features Drivetrain Options: Front-Wheel Drive (FWD) or Audi's legendary Quattro All-Wheel Drive (AWD) Fluid Specifications Manual Transmission Fluid: G 052 729 (or equivalent API GL-4, SAE 75W-90) Automatic Transmission Fluid: G 055 025 (or equivalent ATF fluid meeting VW 501 60 standard) 📐 Dimensions Exterior Sedan Length: 4516 mm (177.8 in) Width: 1772 mm (69.8 in) Height: 1415 mm (55.7 in) Wheelbase: 2613 mm (102.9 in) Exterior Avant Length: 4579 mm (180.3 in) Width: 1772 mm (69.8 in) Height: 1427 mm (56.2 in) Wheelbase: 2613 mm (102.9 in) Weights Curb Weight Min: 1390 kg (3065 lbs) - 1.8T FWD Manual Curb Weight Max: 1550 kg (3417 lbs) - 2.8 Quattro Auto 🛡️ Safety Features Ratings NHTSA Frontal Driver: 5-Star NHTSA Frontal Passenger: 5-Star IIHS Side Impact: Good IIHS Frontal Offset: Acceptable Active Features ABS: Standard Traction Control: Optional (ASR or ESP depending on trim/year) Electronic Stability Program: Available (ESP) Passive Features Airbags Front: Driver and Passenger airbags Airbags Side: Optional front side-impact airbags Seatbelts: Three-point seatbelts with pretensioners front and rear 💡 Technology Features Infotainment Audio System: Audi Concert/Symphony audio systems with CD player or cassette tape, optional CD changer. Navigation: Optional Audi Navigation system. Driver Assistance Cruise Control: Standard on most models. Parking Sensors: Optional rear parking sensors. Connectivity Phone Integration: Optional dealer-installed hands-free phone kits. 🔧 Maintenance Service Intervals Oil Oil Change Interval: Every 7,500 miles (12,000 km) or 12 months, whichever comes first. Flexible interval based on driving conditions can be used with synthetic oil. Oil Specifications Engine Oil 1.8T: SAE 5W-40, API SJ/SL, ACEA A3-98 or VW 502.00 / 505.00 Specification (Synthetic recommended) Engine Oil 2.0: SAE 5W-40, API SJ/SL, ACEA A3-98 or VW 502.00 / 505.00 Specification (Synthetic recommended) Engine Oil 2.8V6: SAE 5W-40, API SJ/SL, ACEA A3-98 or VW 502.00 / 505.00 Specification (Synthetic recommended) Service Intervals Other Timing Belt: Replace timing belt and tensioners every 60,000 miles (96,000 km) or 5 years for 2.8L V6 engines. 1.8T engines utilize a timing chain, which typically has a longer service life but requires periodic inspection. Coolant Flush: Every 30,000 miles (48,000 km) or 2 years. Fluid Capacities Engine Oil Capacity 1.8T: 4.5 Liters (4.8 US Quarts) Engine Oil Capacity 2.8V6: 5.5 Liters (5.8 US Quarts) Known Issues Ignition Coils: Failure of ignition coils is common, leading to misfires. Mass Air Flow Sensor: MAFS can become dirty or fail, causing rough idle and poor performance. ABS Wheel Speed Sensors: Wheel speed sensors...