Market Segment:
Executive/Luxury Sedan
Target Audience:
BMW owners, independent repair shops, automotive technicians specializing in BMW vehicles.
Competitors:
Mercedes-Benz W124 E-Class, Audi 100/200, Volvo 740/940.
Design Philosophy:
Focus on driving dynamics, build quality, and sophisticated engineering.
Target Market Region:
Primarily European market for 520/520i variants, but manual covers broader E34 platform.
Engine Mechanical:
Complete engine overhaul, cylinder head, pistons, crankshaft, camshafts, timing system, lubrication, cooling system, fuel injection (specific to 520i).
Engine Management:
Engine Control Unit (ECU) diagnosis, sensor testing and replacement, ignition system, fuel delivery and control for M50B20 engine.
Transmission:
Manual and automatic transmission overhaul, clutch operation, driveline, driveshafts, differentials.
Suspension:
Front and rear suspension components, shock absorbers, springs, control arms, anti-roll bars, steering system, power steering.
Brakes:
Hydraulic system, ABS (if equipped), brake calipers, rotors, pads, lines, master cylinder, brake fluid specifications.
Electrical System:
Wiring diagrams, battery, charging system (alternator), starting system, lighting, fuses, relays, horn, wipers, power windows, mirrors.
Bodywork:
Body panel removal and installation, doors, hood, trunk, bumpers, glass, interior trim, body repair specifications.
HVAC:
Heating, ventilation, and air conditioning system diagnosis and repair, refrigerant handling.
Fuel System:
Fuel tank, fuel pump, fuel lines, injectors, fuel pressure regulator.
Maintenance:
Routine maintenance schedules, oil changes, filter replacements, spark plug replacement, fluid checks and top-ups.
Troubleshooting:
Diagnostic procedures for common problems, fault finding based on symptoms, specific diagnostic codes (if applicable).
Repair:
Step-by-step repair instructions for all major systems, component replacement, adjustments, and calibrations.
Assembly Disassembly:
Detailed instructions for removing and reassembling various vehicle components and systems.
Depth:
Comprehensive, suitable for professional technicians and advanced DIY enthusiasts. Covers diagnostics, repair, and overhaul.
Diagnostics:
Detailed diagnostic flowcharts and procedures, including electrical system diagnostics.
Engine Type:
Inline 6-cylinder, naturally aspirated petrol
Engine Code Common:
M20B20 (for earlier 520 models) or M50B20 (for 520i, likely from 1990 onwards)
Displacement:
2.0 Liters (1990 cc)
Horsepower M50B20:
Approx. 150 PS (148 hp) @ 6000 rpm
Torque M50B20:
Approx. 190 Nm (140 lb-ft) @ 4300 rpm
Fuel Delivery:
Bosch Motronic fuel injection (specific version dependent on year/engine)
Fuel Type:
Unleaded Petrol (RON 91 or higher)
Valvetrain:
DOHC, 4 valves per cylinder
Crash Test History:
E34 platform generally well-regarded for its era, though formal ratings from independent agencies like NHTSA/IIHS may be limited for this specific generation and model variant.
ABS:
Available, often standard on later models or optional.
Airbags:
Driver airbag standard from 1990/1991, passenger airbag optional/later addition.
Seatbelts:
Three-point front and rear seatbelts.
Oil Change:
Typically every 10,000-15,000 km or 12 months, depending on driving conditions and oil used. Check manual for specific recommendation.
Spark Plugs:
Intervals vary by plug type (copper, platinum, iridium). Typically 20,000-40,000 km for older copper plugs, potentially longer for precious metal types.
Coolant Change:
Every 2-3 years or 40,000-60,000 km.
Brake Fluid Change:
Every 2 years.
Engine Oil:
API SG/SH or higher. Viscosity grades such as 5W-30, 5W-40, 10W-40, or 15W-40 depending on climate. Refer to manual for precise BMW approvals (e.g., BMW Special Oil).
Coolant:
BMW Blue Antifreeze/Coolant (G48) or equivalent ethylene glycol-based coolant, mixed 50/50 with distilled water.
Transmission Fluid Manual:
API GL-4 or GL-5 gear oil, e.g., 75W-90 or 80W-90.
Transmission Fluid Automatic:
ATF Dexron II or III (e.g., ZF Lifeguardfluid 4 or equivalent).
Brake Fluid:
DOT 3 or DOT 4.
Cooling System:
Water pump failure, hose degradation, thermostat issues, radiator leaks.
Engine M50:
VANOS (Variable Valve Timing) unit on M50 engine can develop issues (rattling, poor performance), oil leaks from valve cover gasket and oil pan gasket.
Electrical:
Corrosion in wiring harnesses, failure of headlight motors (E34 specific feature), climate control unit issues, fuel pump relay failures.
Suspension:
Worn control arm bushings, ball joints, and tie rods leading to steering play and uneven tire wear.
Exhaust System:
Corrosion and failure of mufflers and catalytic converters over time.
Bmw Philosophy:
Bayerische Motoren Werke AG, renowned for its focus on sporty driving characteristics, engineering excellence, and premium build quality.
E34 Introduction:
The E34 generation of the BMW 5 Series was introduced in 1987 (as a 1988 model year) and replaced the E28. It marked a significant step forward in design and technology.
520 520I Positioning:
The 520 and 520i variants were typically entry-level models within the 5 Series lineup, often targeting markets with higher vehicle taxes on larger displacements. They offered a balance of BMW's signature driving feel with a more accessible 2.0-liter engine.
Production Period:
E34: 1987-1996. This manual covers the early phase of the E34 generation.
Manufacturing Locations:
Primarily Germany (Dingolfing plant).
