Vehicle Class:
Compact Executive Sports Sedan/Coupe
Target Audience:
Enthusiasts, DIY mechanics, professional workshops specializing in BMW vehicles.
Key Competitors:
Mercedes-Benz 190E, Audi 80/90, Alfa Romeo 75, Ford Sierra Cosworth (in certain markets).
Vehicle Strengths:
Renowned driving dynamics, balanced chassis, reliable inline-six engines, build quality, sporty styling.
Manual Value Proposition:
Enables owners and technicians to maintain and repair these classic BMWs to factory specifications, preserving their performance and value.
Engine:
Complete engine overhaul, diagnosis, tuning, emission controls, cooling system, lubrication system, fuel system (EFI), intake and exhaust systems.
Transmission:
Manual and Automatic transmission service, repair, overhaul, diagnosis, and fluid specifications.
Drivetrain:
Driveshafts, CV joints, differential, rear axle assembly.
Suspension:
Front and rear suspension components, steering system, alignment specifications, shock absorbers, springs, bushings.
Brakes:
Front and rear brake systems (disc brakes), ABS (where applicable), brake fluid specifications, caliper and master cylinder overhaul, bleeding procedures.
Electrical:
Complete wiring diagrams, component testing, battery, alternator, starter, ignition system, lighting, instrumentation, fuses, relays, ECU (DME).
Bodywork:
Body panel removal and installation, interior trim, glass, seals, doors, hood, trunk.
HVAC:
Heating, Ventilation, and Air Conditioning system service and repair.
Fuel System:
Fuel pump, injectors, fuel pressure regulator, fuel tank, emissions control system.
Cooling System:
Radiator, water pump, thermostat, hoses, coolant specifications.
Maintenance:
Routine scheduled maintenance, oil changes, filter replacements, tune-ups, fluid checks and changes.
Troubleshooting:
Diagnostic procedures for common and complex issues, symptom-based troubleshooting charts.
Repair:
Step-by-step repair instructions for all major components and systems.
Overhaul:
Complete engine and transmission rebuild procedures.
Diagnosis:
Electrical system diagnostics, engine performance diagnostics.
Installation:
Component replacement and installation guidelines.
Depth:
Comprehensive workshop level, covering everything from basic maintenance to complete engine and transmission rebuilds, including detailed diagnostic procedures and wiring diagrams.
Type:
Digital (PDF likely, known for searchable text and high resolution for diagrams)
Diagram Clarity:
High resolution, allowing for clear viewing of detailed schematics and illustrations.
Text Readability:
Clear and legible, suitable for on-screen reading and potential printing.
For Digital:
Not applicable (digital format)
For Digital:
Not applicable (digital format)
Engine Code:
M20B27 (for 325i/325is/325e variants, though this manual covers the 2.5L version)
Engine Type:
Inline 6-cylinder, SOHC
Displacement:
2494 cc (2.5 Liters)
Bore X Stroke:
84 mm x 75 mm
Horsepower:
168 hp @ 5800 rpm (Euro spec), 168 hp @ 5800 rpm (US spec, after 1988 update)
Torque:
225 Nm (166 lb-ft) @ 4300 rpm (Euro spec), 225 Nm (166 lb-ft) @ 4300 rpm (US spec, after 1988 update)
Fuel Delivery:
Bosch Motronic Electronic Fuel Injection (EFI)
Fuel Type:
Unleaded Gasoline (Premium)
NHTSA Crash Test Results:
Not specifically rated by modern standards due to era of manufacture, but E30 chassis was known for robust construction.
ABS:
Anti-lock Braking System (ABS) available as an option, standard on some later models/trims.
Traction Control:
Not commonly available on this generation, some later models may have had ASC (Automatic Stability Control) as a very rare option.
Seatbelts:
Three-point seat belts with pretensioners (front), lap belts (rear).
Airbags:
Driver's side airbag became available on later models (late 1990-1991 MY) as an option.
Body Structure:
Reinforced safety cage, crumple zones.
Audio System:
Factory cassette player with AM/FM radio, optional CD player for later models. Basic speaker setup.
Climate Control:
Manual climate control with heater and A/C (optional). Recirculation button common.
Cruise Control:
Optional on many models, typically vacuum-operated or electronic.
Onboard Computer:
Basic OBC (On-Board Computer) on some models, providing fuel consumption and range information.
Early Features:
Limited by era; primarily analog systems. No modern Bluetooth or USB connectivity.
Oil Change:
Every 7,500-10,000 miles or 12-18 months, whichever comes first (depending on driving conditions and oil used).
Air Filter:
Inspect every 15,000 miles, replace as needed or every 30,000 miles.
Spark Plugs:
Replace every 30,000 miles for standard plugs, or as recommended for platinum/iridium types if retrofitted.
Coolant Flush:
Every 2-3 years or 30,000-45,000 miles.
Timing Belt:
The M20 engine uses a timing belt. Replacement interval is typically 50,000-60,000 miles or 5 years. Critical to adhere to this to prevent catastrophic engine damage.
Engine Oil:
API SG or higher, SAE 15W-40 or 10W-40 recommended for most climates. Consult manual for specific viscosity. Capacity: Approx. 4.25 liters (4.5 US quarts) with filter.
Coolant:
BMW Blue Antifreeze/Coolant or equivalent ethylene glycol-based coolant with corrosion inhibitors. Typically a 50/50 mix with distilled water. Capacity: Approx. 7 liters.
Brake Fluid:
DOT 3 or DOT 4 brake fluid. Must be replaced every 2 years due to hygroscopic nature.
Transmission Fluid Manual:
API GL-4 or GL-5 SAE 75W-90 gear oil. Capacity: Approx. 1.5 liters.
Transmission Fluid Automatic:
Dexron II or equivalent ATF. Capacity: Approx. 1.5 liters for a drain and fill.
Differential Fluid:
API GL-5 SAE 75W-90 gear oil. Capacity: Approx. 1.3 liters.
Engine:
Oil leaks from valve cover gasket and oil pan gasket; coolant leaks from hoses, water pump, and thermostat housing; idle control valve issues; fuel injector clogging; starter motor failure.
Suspension Steering:
Worn control arm bushings (lollipop bushings), worn sway bar links, worn ball joints, steering rack leaks, strut mount wear.
Electrical:
Fuse box corrosion/failure; alternator issues; starter solenoid failure; dashboard warning light issues; wiring harness degradation (especially in engine bay).
Body Interior:
Rust (especially around wheel arches, rocker panels, and sunroof); headliner sagging; door seal deterioration; dashboard cracks.
Bmw Legacy:
BMW has a long-standing reputation for building driver-focused, high-performance vehicles with excellent engineering and build quality.
E30 Introduction:
The E30 generation of the 3 Series was introduced in 1982 as the successor to the E21. The 325 model line evolved from the 323i and introduced the M20 'Super Eta' engine, later the M20B25.
Facelifts Updates:
The E30 received a significant facelift in late 1987 (for the 1988 model year), including updated bumpers ('I-Design' or 'Euro bumpers'), revised taillights, and some interior tweaks. The 325i model specifically benefited from the introduction of the more potent 2.5L M20B25 engine.
Production Years:
1987-1991 (for the 325/325i E30 models covered by this manual)
Manufacturing Locations:
Primarily Germany.
