Positioning:
The BMW E21 3 Series represented BMW's entry into the compact executive sports sedan market, a segment it would come to define.
Competitors:
Competed against vehicles like the Mercedes-Benz 190, Alfa Romeo Alfetta, and Ford Capri.
Design Philosophy:
Focus on driver engagement, balanced chassis, and premium feel in a smaller package.
Engine Options:
Offered a range of efficient 4-cylinder (M10) and powerful 6-cylinder (M20) engines, establishing BMW's reputation for performance.
Coverage:
All Models, Engines, Trim, and Transmission Types within the E21 generation
Page Count Estimate:
Estimated 1500-2000+ pages (typical for comprehensive workshop manuals of this era)
Type:
Complete Workshop Service Repair Manual
Format:
Downloadable Digital Format (PDF)
Engine:
Detailed service, repair, and diagnostic procedures for all M10 (4-cylinder) and M20 (6-cylinder) engines fitted to the E21 chassis.
Fuel System:
Carburetor systems (Zenith, Solex) and early Bosch K-Jetronic fuel injection systems.
Ignition System:
Distributor-based ignition systems, coil, spark plugs, and related components.
Cooling System:
Radiator, fan, water pump, thermostat, hoses, and coolant specifications.
Exhaust System:
Exhaust manifold, catalytic converter (on later models), muffler, and pipework.
Transmission:
Manual transmissions (4-speed and 5-speed) and automatic transmissions (3-speed).
Drivetrain:
Clutch operation, driveshafts, differential, and rear axle assembly.
Suspension:
Front MacPherson struts, rear semi-trailing arms, shock absorbers, springs, bushings, and alignment procedures.
Brakes:
Front disc brakes, rear drum brakes (or optional rear discs on some models), brake hydraulics, and bleeding procedures.
Steering:
Steering gear, steering column, and power steering systems (if equipped).
Electrical System:
Battery, alternator, starter motor, lighting systems, fuses, relays, and wiring diagrams.
Body:
Body panel removal/installation, door mechanisms, glass replacement, interior trim, and basic bodywork repair.
Heating And Ventilation:
Heater core, blower motor, and ventilation system components.
Maintenance:
Routine maintenance tasks such as oil changes, filter replacements, spark plug service, coolant flushes, and brake fluid changes.
Troubleshooting:
Diagnostic charts and symptom-based troubleshooting for common issues across all vehicle systems.
Repair:
Step-by-step instructions for component removal, disassembly, repair, reassembly, and installation.
Overhaul:
Complete engine and transmission overhaul procedures, including specifications for machining and assembly.
Wiring Diagrams:
Comprehensive electrical schematics for all vehicle systems.
Depth:
Comprehensive, covering everything from basic maintenance to complete engine and transmission rebuilds, including advanced diagnostics and component-level repair.
Engine Family:
M10 (4-cylinder) and M20 (6-cylinder)
Engine Displacement Options:
1.8L (M10), 2.0L (M10), 2.3L (M20), 2.5L (M20)
Horsepower Range:
Approximately 90 hp (2.0L M10) to 143 hp (2.3L M20) depending on engine variant and market.
Torque Range:
Approximately 118 lb-ft (2.0L M10) to 153 lb-ft (2.3L M20) depending on engine variant.
Injection System:
Carburetor (Zenith 35/40 INAT, Solex 32/36 DGAV) and Bosch L-Jetronic / K-Jetronic fuel injection (on later models and higher trims like 320i, 323i).
Cylinder Configuration:
Inline 4-cylinder and Inline 6-cylinder
Timing Belt Interval:
Refer to manual, typically 40,000 - 60,000 miles for M10, M20 engines (with chain for M20 on later models).
Standard Transmission:
4-speed manual
Optional Transmission:
5-speed manual and 3-speed ZF automatic transmission
Clutch Type:
Single dry plate, hydraulically operated clutch
Manual Transmission Fluid:
GL-4 SAE 75W-90 or SAE 80W-90 gear oil
Automatic Transmission Fluid:
Dexron II (or equivalent)
Wheelbase:
Approx. 2570 mm (101.2 in)
Length:
Approx. 4390 mm (172.8 in)
Width:
Approx. 1610 mm (63.4 in)
Height:
Approx. 1380 mm (54.3 in)
Curb Weight:
Approx. 1100-1300 kg (2425-2866 lbs), depending on engine and equipment
Wheel Bolt Pattern:
4x100
Standard Tire Size:
165 R13, 175/70 R13, 185/70 R13 (depending on model and year)
Crash Test Data:
Limited formal crash test data available from this era, but designed with crumple zones and a strong safety cage typical of BMW.
Braking System:
Front ventilated disc brakes, rear drum brakes; optional rear disc brakes on some models. Vacuum-assisted brake booster.
Seatbelts:
3-point front seatbelts, 2-point rear seatbelts (later models often featured 3-point rear belts).
Steering Column:
Collapsible steering column for improved driver safety.
Oil Change Interval:
Approximately every 5,000-7,500 miles or 6-12 months, depending on driving conditions and oil type.
Air Filter Replacement:
Refer to manual, typically 15,000-30,000 miles.
Spark Plug Replacement:
Refer to manual, typically 20,000-40,000 miles, depending on plug type.
Engine Oil:
API SF/SG or higher. Viscosity: 10W-40, 15W-40, or 20W-50 depending on climate. See manual for exact specifications.
Coolant:
Ethylene glycol-based coolant (e.g., BMW blue coolant or compatible equivalent) mixed 50/50 with distilled water.
Brake Fluid:
DOT 3 or DOT 4 brake fluid.
Rust:
Common rust areas include wheel arches, rocker panels, door bottoms, and trunk floor.
Cooling System:
Aging rubber hoses, leaking radiators, and water pump failures.
Fuel System:
Carburetor tuning issues, worn fuel pumps, and deteriorating fuel lines.
Electrical:
Corroded grounds, aging wiring harnesses, and faulty ignition components.
