🏷️ Basic Information Identification Make: Porsche Model: 928 S / S4 Model Years Covered: 1985, 1986, 1987, 1988, 1989 Codes Vehicle Platform: Type 928 👋 Introduction Market Position Vehicle Segment: Grand Tourer (GT) Competitive Analysis Key Competitors: Ferrari 412, Aston Martin V8 Vantage, Jaguar XJS, Maserati Quattroporte Key Features Design Philosophy: Front-engine, rear-wheel drive, V8 powered luxury sports coupe with advanced engineering for its time. Dvp Philosophy: Focus on technical accuracy and comprehensive coverage for expert and enthusiast use. 📋 Manual Details Coverage Areas Technical Manual Type: Factory Service Manual / Technical Data Manual Page Count Estimated Page Count: Over 800 pages (typical for this era's comprehensive manuals) Manual Type Manual Format: Digital Download (PDF) Language Language: English Format Digital Format: Printable PDF 📖 Manual Coverage Systems Covered Powertrain: Engine (V8), Fuel System, Ignition System, Exhaust System, Cooling System, Lubrication System Transmission: Automatic Transmission (Tiptronic optional on later S4 models), Clutch, Driveshafts, Differential Chassis: Suspension (Front and Rear), Steering, Brakes (Front and Rear), Wheels, Tires Electrical: Wiring Diagrams, Starting System, Charging System, Lighting, Instrumentation, Body Electrics, HVAC Electronics, ABS (where applicable) Body: Body Panels, Doors, Hood, Trunk, Glass, Interior Trim, Body Repair Procedures Procedures Included Routine Maintenance: Oil Changes, Filter Replacements, Spark Plug Service, Air Filter Service, Coolant Flush, Brake Fluid Service, Belt Inspection/Replacement Troubleshooting: Diagnostic Flowcharts, Symptom-Based Diagnostics, Fault Code Interpretation (where applicable) Repair And Rebuild: Engine Overhaul, Transmission Rebuild, Suspension Component Replacement, Brake Caliper Rebuild, Electrical Component Repair Technical Specifications: Torque Specifications, Clearances, Tolerances, Diagnostic Values Technical Depth Diagnostic Capabilities: Advanced Diagnostics for Engine Management, Fuel Injection, and ABS Systems Repair Scope: Comprehensive from basic fluid changes to complete engine and transmission overhauls Electrical Diagrams: Detailed, system-specific wiring schematics with component locations 📊 Manual Specifications File Format PDF Quality: High-resolution, searchable text for easy navigation and printing Print Quality Printability: Designed for selective printing of relevant sections Binding Type Digital Access: Instant download, no physical binding Paper Type Digital Media: Electronic document ⚙️ Engine Specifications Primary Engine Engine Type: Naturally Aspirated V8 Engine Displacement Liters 1985 1986: 4.7 L (4663 cc) Engine Displacement Liters 1987 1989: 5.0 L (4982 cc) Performance Horsepower 1985 1986: 256 hp @ 5500 rpm (US Spec) Horsepower 1987 1989: 315 hp @ 5700 rpm (US Spec) Torque Ft Lbs 1985 1986: 293 lb-ft @ 3000 rpm (US Spec) Torque Ft Lbs 1987 1989: 340 lb-ft @ 4500 rpm (US Spec) Fuel System Fuel Injection: Bosch L-Jetronic (1985-1986), Bosch DME (Digital Motor Electronics) with K-Jetronic injection (1987-1989 S4) Fuel Type: Premium Unleaded Gasoline 🔧 Transmission Standard Transmission Type 1985 1986: 4-Speed Automatic (Automatic Transmission, standard) Transmission Type 1987 1989: 3-Speed Automatic (standard, with optional 4-speed 'Tiptronic' on some S4 models) Optional Manual Transmission: 5-Speed Manual Transmission (available on select models, less common in US market) Features Transmission Fluid Type: Dexron III or equivalent (consult manual for specific PN and capacity) 📐 Dimensions Exterior Length Mm: 4655 mm (1985-1986), 4680 mm (1987-1989) Width Mm: 1785 mm Height Mm: 1280 mm Weights Curb Weight Kg: Approximately 1500-1600 kg (depending on specification) 🛡️ Safety Features Ratings Crash Test Results: Not extensively tested by modern standards, but known for robust body structure. Active Features Anti Lock Brakes: ABS standard on S4 models, optional on later 928 S models Passive Features Airbags: Driver airbag standard on S4 models, passenger airbag optional/not typically present on earlier 928 S models. 💡 Technology Features Infotainment Audio System: Premium sound systems, often with cassette player and optional CD changer. Later models featured improved stereo options. Driver Assistance Cruise Control: Standard on most models Connectivity Telematics: Basic for the era, no modern smartphone integration or advanced connectivity features. 🔧 Maintenance Service Intervals Oil Change Interval Km: 10,000 km or 12 months (whichever comes first) Timing Belt Replacement Km: 50,000 km or 5 years (critical maintenance item) Fluid Specifications Engine Oil Type Viscosity: Mobil 1 15W-50 or equivalent (consult manual for precise OEM spec and capacity) Coolant Type: Porsche G48 (or equivalent ethylene glycol based coolant with corrosion inhibitors) Known Issues Common Problems: Timing belt failure (if not replaced per schedule), ignition system component wear, fuel injector issues, aging rubber hoses and seals, HVAC system issues, automatic transmission control unit failures. Preventative Maintenance: Adherence to timing belt replacement schedule is paramount. Regular inspection of hoses, belts, and vacuum lines. 📚 Vehicle History Brand Heritage Porsche Legacy: Porsche's flagship luxury grand tourer, designed as a potential successor to the 911. Model Evolution 928 Development: Introduced in 1977, the 928 evolved significantly through its production run, with the 'S' and 'S4' designations marking key performance and feature upgrades. Production Production Period: 1978-1995 (with significant variations in specifications across model years). Factory Location: Stuttgart, Germany 🏆 Awards & Recognition Recognitions Automotive Design: Often praised for its innovative transaxle design and aerodynamic styling, considered a modern classic.