🏷️ Basic Information Identification Make: Porsche Model: 928 S Model Year: 1985 Generation: Second Generation (928 S) Codes Internal Model Code: Type 928 👋 Introduction Market Position Historical Significance: The Porsche 928 was a groundbreaking luxury grand tourer from Porsche, featuring a front-engine, rear-transaxle layout and V8 power, differentiating it from the marque's traditional rear-engine sports cars. Competitive Analysis Market Segment: Competed with other high-performance GT cars of its era, such as the Jaguar XJS, Aston Martin V8 Vantage, and potentially lower-end Ferrari models. Key Features Model Year Highlights: The 1985 model year introduced significant updates to the S model, often including improved engine performance and refinement over earlier versions. Manual Value Proposition Usefulness For Owners: Essential for diagnosing and repairing complex electrical issues common in sophisticated European cars of this era, particularly for owners seeking to maintain originality or undertake DIY repairs. Usefulness For Technicians: Indispensable tool for independent repair shops and Porsche specialists working on the 928. 📋 Manual Details Coverage Areas Primary Coverage: Electrical System Wiring Diagrams Secondary Coverage: Component Integration and Location Page Count Estimated Page Count: Varies by specific publication; typically 50-150 pages for a dedicated wiring diagram manual. Manual Type Manual Type: Wiring Diagram Manual / Electrical Troubleshooting Manual Language Language: English (Standard for this market) Format Format: Likely Printed Booklet or Digital PDF 📖 Manual Coverage Systems Covered Lighting System: Headlamps (High/Low Beam), Tail Lamps, Brake Lamps, Turn Signals, Parking Lamps, Fog Lamps, Interior Lighting (Dome, Map, Glovebox, Ash Tray). Body Electrical: Power Windows, Power Door Locks, Central Locking System, Mirrors (Power Adjustment/Defrost), Wipers (Front/Rear), Washers, Horn, Sunroof/Moonroof Operation (if equipped). Instrument Cluster And Indicators: Speedometer, Tachometer, Fuel Gauge, Oil Pressure Gauge, Coolant Temperature Gauge, Oil Temperature Gauge, Voltmeter, Warning Lamps (Brake, Oil Pressure, Charging System, ABS, Airbag - if equipped), Turn Signal Indicators, High Beam Indicator. HVAC System: Blower Motor, Heater Core Control Valve, Air Conditioning Compressor Clutch, Mode Selector Controls, Temperature Control System (manual or automatic climate control specific wiring). Audio System: Factory Radio/Cassette Player Wiring, Amplifier Connections (if applicable), Speaker Wiring. Safety Systems: Anti-lock Braking System (ABS) Module and Sensor Wiring, Alarm System Wiring, Trailer Coupling Electrical Interface (if factory option). Engine Electronics: Digital Engine Electronics (DME) Harnesses, Fuel Injection System Wiring, Ignition System Wiring, Sensors (Crankshaft Position, Camshaft Position, Throttle Position, Knock, Lambda/Oxygen), Fuel Pump Control, Idle Control Valve. Central Electrical System: Fuse Boxes, Relay Locations and Function, Battery Connections, Grounding Points, Power Distribution. Procedures Included Troubleshooting Guidance: Interpreting Circuit Diagrams, Identifying Wire Colors and Functions, Locating Components, Common Fault Diagnosis based on electrical symptoms. Component Location: Diagrams showing the physical location of fuses, relays, control modules, sensors, and actuators. Wiring Repair: Guidance on proper splicing, connector repair, and wire harness maintenance (though often implied through diagram clarity). Technical Depth Detail Level: High-Level Detail: Comprehensive circuit diagrams with wire colors, pin assignments, component identification, and connector views. Diagnostic Focus: Primarily focused on electrical system diagnostics and repair, not mechanical repairs. System Interconnectivity: Illustrates how different electrical systems interface with each other. 📊 Manual Specifications File Format Digital Format Quality: If PDF, expect high-resolution scans of original factory diagrams, ensuring clarity and readability. Print Quality Printed Format Quality: Typically printed on durable paper stock with clear line work and legible text. Binding Type Printed Binding: Often spiral-bound or saddle-stitched for ease of use when laid flat. Paper Type Printed Paper Type: Durable paper stock, often with a matte finish to reduce glare. ⚙️ Engine Specifications Primary Engine Engine Type: V8, naturally aspirated Displacement: 4.7 Liters (4664 cc) Engine Code Variant: M28/10 (approximate for 1985 S models, specific variants exist) Performance Horsepower: Approximately 250-280 hp (SAE net, depending on market and specific tune) Torque: Approximately 295-330 lb-ft (SAE net, depending on market and specific tune) Fuel System Fuel Delivery: Bosch L-Jetronic Fuel Injection Fuel Type: Premium Unleaded Gasoline Ignition System Ignition Type: Distributorless Ignition System (DIS) with Electronic Control Unit (ECU) 🔧 Transmission Standard Transmission Type: 5-Speed Manual Transaxle Optional Transmission Type: 3-Speed Automatic Transaxle (e.g., Automatic Transaxle Model 090) Features Layout: Rear Transaxle (clutch and gearbox located at the rear axle) Fluid Specifications Manual Transmission Fluid: Porsche spec. G 50 (or equivalent GL-4) Gear Oil, typically 75W-90 or 80W-90. Automatic Transmission Fluid: Dexron II or III (or equivalent) 📐 Dimensions Exterior Length: Approx. 179.9 inches (4570 mm) Width: Approx. 71.1 inches (1806 mm) Height: Approx. 50.0 inches (1270 mm) Wheelbase: Approx. 98.4 inches (2500 mm) Weights Curb Weight: Approx. 3,500 - 3,700 lbs (1588 - 1678 kg), depending on transmission and options. Gross Vehicle Weight Rating: Approx. 4,450 lbs (2018 kg) 🛡️ Safety Features Ratings Historical Safety Testing: While formal crash test ratings (like NHTSA or IIHS) were less standardized in the early 80s, the 928 was engineered with a strong safety cell and considered a very safe vehicle for...