🏷️ Basic Information Identification Make: Porsche Model: 928 Model Variant: S, S4, GT, GTS Model Years Covered: 1989 Codes Engine Code S4: M28/42 Engine Code Gt: M28/46 Engine Code Gts: M28/46 (modified) 👋 Introduction Market Position Market Position: The Porsche 928 was a luxury grand tourer, a departure from Porsche's traditional sports car lineage, offering a front-engine, rear-wheel-drive configuration with a V8 engine and advanced technology for its era. Competitive Analysis Competitors: Competed with luxury GTs like the Jaguar XJS, Aston Martin Vantage, and BMW 8 Series. Key Features Key Features Of 928: Transaxle design (engine in front, gearbox in rear for balanced weight distribution), V8 engine, advanced suspension, comfortable interior, hatchback body style. Manual Value Manual Utility: Essential for maintaining and repairing the complex systems of the Porsche 928, providing factory-level accuracy for technicians and enthusiasts. 📋 Manual Details Coverage Areas Systems Covered: Engine (mechanical & electrical), Fuel System, Ignition System, Cooling System, Lubrication System, Exhaust System, Clutch, Transmission (Manual & Automatic), Drive Shafts, Differential, Suspension (Front & Rear), Steering System, Brakes (Front & Rear), Wheels & Tires, Body & Chassis, Electrical System (lighting, instruments, comfort features), Climate Control, Fuel Injection System, Air Conditioning Page Count Estimated Page Count: 1000+ Manual Type Manual Type: Workshop Manual / Service Manual / Repair Manual Language Language: English Format Format: Digital Download (PDF) 📖 Manual Coverage Systems Covered Engine Mechanical: Detailed overhaul procedures for cylinder heads, pistons, crankshaft, camshafts, timing belt system, valve train. Engine Electrical: Comprehensive wiring diagrams, diagnostic procedures for DME (Digital Motor Electronics), ignition system, sensors, actuators. Fuel System: Bosch L-Jetronic (S4) and Motronic (GT/GTS) fuel injection system diagnosis, fuel pump, injectors, fuel pressure regulator. Transmission Automatic: Detailed procedures for ZF 4HP-22 automatic transmission (S4) and 4HP-24 (GT/GTS) including overhaul, adjustments, and troubleshooting. Suspension And Steering: Front Transaxle and Rear Suspension (independent), power steering system diagnosis and repair. Brakes: Front and rear disc brake systems, ABS (Anti-lock Braking System) diagnosis and components. Procedures Included Preventive Maintenance: Scheduled maintenance intervals, fluid checks and changes, filter replacements, lubrication points. Troubleshooting: Systematic diagnostic charts and flowcharts for common issues and fault finding. Repair And Overhaul: Step-by-step instructions for component removal, disassembly, inspection, repair, reassembly, and installation. Technical Specifications: Torque specifications for all fasteners, clearance measurements, timing specifications, diagnostic values. Technical Depth Depth: Comprehensive, covering basic maintenance to complete engine and transmission rebuilds, detailed electrical diagnostics, and bodywork repair. 📊 Manual Specifications File Format File Format: PDF Print Quality Print Quality: High-resolution, clear text and legible diagrams suitable for printing. Binding Type Binding Type: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Type S4: 4.7L V8 SOHC (24 valves) Engine Type Gt Gts: 5.0L V8 SOHC (32 valves) - enlarged displacement and revised cylinder heads for GT/GTS Performance Horsepower S4: 316 hp @ 6000 rpm Torque S4: 315 lb-ft @ 3000 rpm Horsepower Gt: 326 hp @ 6000 rpm Torque Gt: 339 lb-ft @ 3000 rpm Horsepower Gts: 350 hp @ 5700 rpm Torque Gts: 369 lb-ft @ 4500 rpm Fuel System Fuel Injection S4: Bosch L-Jetronic Fuel Injection Gt Gts: Bosch Motronic (M2.7 for GT, M6.1 for GTS) Fuel Type: Premium Unleaded Gasoline (91 Octane or higher) 🔧 Transmission Standard Transmission S4: 4-speed Automatic (ZF 4HP-22) Optional Transmission Gt Gts: 5-speed Manual (Porsche G28/11 for GT, G28/15 for GTS) Features Transmission Fluid Type Auto: Dexron III or equivalent (check specific service bulletin for Porsche approved fluid) Transmission Fluid Capacity Auto: Approx. 8-10 liters (varies based on conversion) Clutch Type: Single dry plate (for manual transmission models) 📐 Dimensions Exterior Length: 4655 mm (183.3 in) Width: 1785 mm (70.3 in) Height: 1280 mm (50.4 in) Wheelbase: 2550 mm (100.4 in) Weights Curb Weight S4 Auto: Approx. 1650 kg (3638 lbs) Curb Weight Gts Manual: Approx. 1620 kg (3571 lbs) Cargo Cargo Volume: Approx. 0.37 m³ (13.1 cu ft) with rear seats up 🛡️ Safety Features Ratings Safety Ratings: Not applicable (vehicles of this era were not typically subjected to standardized crash tests like modern vehicles). Active Features ABS: Standard on S4, GT, and GTS models (Bosch ABS II) Passive Features Passive Safety: Three-point seat belts, padded dashboard, energy-absorbing steering column. 💡 Technology Features Infotainment Infotainment Features: Factory-installed premium audio system (often Blaupunkt or Becker), analog gauges, cassette player. Driver Assistance Driver Assistance Features: ABS (Anti-lock Braking System) was a significant technological advancement for its time. Connectivity Connectivity Features: Limited by modern standards; primarily focused on vehicle operation and basic comfort features. 🔧 Maintenance Service Intervals Oil Change Interval: Every 7,500 miles or 12 months, whichever comes first. Timing Belt Replacement: Every 30,000 miles or 3 years (critical for V8 engine) Transmission Fluid Change Interval: Every 30,000 miles or 2 years (automatic transmission) Fluid Specifications Engine Oil Spec: API SG or SH, SAE 5W-40 or 10W-40...