🏷️ Basic Information Identification Make: BMW Model: 3 Series Model Variant: 320i Codes Chassis Code: E21 Generation Generation Designation: First Generation E21 Production Years Covered: 1975-1984 👋 Introduction Market Position Market Segment: Compact executive sports sedan Target Audience: Enthusiasts, DIY mechanics, owners seeking to maintain and repair their classic BMW Competitive Analysis Key Competitors: Mercedes-Benz W123 (240D, 230E), Audi 80/Fox, Alfa Romeo Alfetta, Ford Sierra Key Features Vehicle Philosophy: Driver-focused, balanced handling, quality engineering Manual Value Proposition: Provides detailed, expert guidance for maintaining and repairing the iconic E21 3 Series 📋 Manual Details Coverage Areas Manual Type: Workshop Service Repair Manual Language: English Format: PDF Page Count Page Count: 910 📖 Manual Coverage Systems Covered Engine: M10 engine family, including M10B20 (2.0L inline-4) Fuel System: Bosch L-Jetronic fuel injection system, fuel pump, injectors, lines, tank Ignition System: Electronic ignition, distributor, coil, spark plugs, wiring Transmission: 4-speed and 5-speed manual transmissions, clutch system, driveshafts Suspension: Front MacPherson struts, rear semi-trailing arms, springs, dampers, bushings Brakes: Front disc brakes, rear drum brakes, hydraulic system, parking brake Steering: Recirculating ball steering system, steering column, linkages Electrical System: 12V system, alternator, starter motor, battery, lighting, fuses, relays, wiring diagrams Cooling System: Radiator, fan, thermostat, water pump, coolant passages Exhaust System: Exhaust manifold, catalytic converter (later models), muffler, pipes Body And Chassis: Unibody construction, body panels, doors, hood, trunk, interior trim HVAC: Heater core, ventilation system, controls Procedures Included Maintenance: Oil changes, filter replacements, spark plug checks, fluid checks and changes Troubleshooting: Diagnostic procedures for engine performance, electrical faults, and mechanical issues Repair: Step-by-step instructions for component replacement and repair across all systems Overhaul: Engine and transmission overhaul procedures Adjustment: Valve clearance adjustment, ignition timing adjustment, carburetor/fuel injection tuning Specifications: Torque specifications for critical fasteners, clearances, fluid capacities, and wear limits Technical Depth Depth: Comprehensive, covering routine maintenance to complete engine and transmission rebuilds 📊 Manual Specifications File Format File Type: PDF Searchability: Searchable text for quick information retrieval Print Quality Resolution: High-resolution scans ensuring clarity of diagrams and text Binding Type Binding: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Code: M10B20 Engine Type: Inline 4-cylinder, SOHC Displacement: 1990 cc (2.0 Liters) Performance Horsepower: 115 PS (113 hp) at 5800 rpm (approximate, varies by market/emission standards) Torque: 165 Nm (122 lb-ft) at 3500 rpm (approximate) Fuel System Fuel Delivery: Bosch L-Jetronic Electronic Fuel Injection Fuel Type: Unleaded gasoline (minimum 91 RON recommended) Engine Management Engine Control Unit: Bosch Motronic (integrated ignition and fuel management in later versions) 🔧 Transmission Standard Type: 4-speed Manual Optional Type: 5-speed Manual, 3-speed ZF Automatic (optional) Features Clutch Type: Single dry plate diaphragm spring clutch Gear Ratios: Specific gear ratios provided in manual for each transmission type Fluid Specifications Manual Transmission Fluid: API GL-4, SAE 75W-90 or 80W-90 (check manual for exact BMW specification) Automatic Transmission Fluid: Dexron II or equivalent (for automatic models) 📐 Dimensions Exterior Wheelbase: 2563 mm (100.9 in) Length: 4355 mm (171.5 in) Width: 1695 mm (66.7 in) Height: 1380 mm (54.3 in) Weights Curb Weight: 1150 kg (2535 lbs) (approximate, varies by equipment) Gross Vehicle Weight Rating: Refer to vehicle identification plate or manual Tires And Wheels Standard Tire Size: 175/70 HR 13 Wheel Bolt Pattern: 4x100 Wheel Offset: ET18 to ET20 (typical for 13-inch wheels) 🛡️ Safety Features Ratings Crash Test Ratings: N/A (No standardized ratings available for this era) Active Features Brakes: Front ventilated disc brakes, rear drum brakes Steering: Recirculating ball steering (non-power assisted standard, power assisted optional on later models) Passive Features Seatbelts: Three-point front seatbelts, two-point rear seatbelts (three-point rear optional/market dependent) Body Structure: Reinforced passenger cell, crumple zones 💡 Technology Features Infotainment Radio: Factory fitted radio (often Blaupunkt or Becker) with AM/FM, cassette player available on later models. Driver Assistance ABS: Anti-lock Braking System (ABS) was optional and became more common on later production years, especially on higher trims. Connectivity Connectivity Features: None by modern standards; focused on mechanical and driver feedback. 🔧 Maintenance Service Intervals Oil Change Interval: Every 5,000-7,500 miles (8,000-12,000 km) or annually (refer to manual for specific recommendation) Filter Replacement Interval: Oil filter with every oil change; air filter and fuel filter every 15,000-30,000 miles (24,000-48,000 km) Timing Belt Chain: M10 engines use a timing chain, which is generally maintenance-free but requires inspection for wear/stretch. Fluid Specifications Engine Oil Type: API SG/SH, SAE 15W-40 or 10W-40 (check manual for specific BMW recommendation, synthetic blends are beneficial) Coolant Type: Ethylene glycol based antifreeze, mixed 50/50 with distilled water Brake Fluid Type: DOT 4 Power Steering Fluid: ATF Dexron II (if equipped with power steering) Known Issues Engine Mounts: Wear and degradation leading to vibration and noise. Rust: Common on wheel arches, sills, door bottoms, and trunk floor. Fuel Lines: Degradation of rubber fuel lines and fittings over...