Segment:
Compact executive sports sedan
Target Audience:
Enthusiasts and owners seeking to perform their own maintenance and repairs on a classic BMW.
Competitors:
Mercedes-Benz 190E, Audi 80/90, Alfa Romeo 75, Saab 900
Performance Appeal:
Renowned for its balanced chassis, engaging driving dynamics, and reliable inline-six engines.
Design Language:
Classic BMW 'Bangle' era design with clean lines and a driver-focused interior.
Engine:
M20B25 2.5L inline-six engine (including fuel injection, ignition, cooling, lubrication, exhaust)
Transmission:
Getrag 260 5-speed manual and ZF 4HP22 4-speed automatic transmission (including overhaul, diagnosis, fluid specs)
Drivetrain:
Rear-wheel drive, limited-slip differential (LSD) options, driveshafts, CV joints
Suspension:
Front MacPherson struts, rear semi-trailing arms, springs, dampers, bushings, anti-roll bars
Brakes:
Front ventilated discs, rear solid discs (ABS system), brake hydraulics, parking brake
Steering:
Power-assisted rack and pinion steering system
Electrical System:
12V system, alternator, starter, battery, wiring diagrams, fuses, relays, lighting, instrumentation
Fuel System:
Bosch Motronic fuel injection, fuel pump, injectors, fuel filter, fuel tank
Cooling System:
Radiator, fan, water pump, thermostat, coolant hoses
Exhaust System:
Exhaust manifolds, catalytic converter, mufflers, pipes
Body And Chassis:
Body panels, doors, hood, trunk, glass, frame, rust prevention
HVAC:
Heating, ventilation, and air conditioning system components and operation
Maintenance:
Scheduled maintenance, oil changes, fluid checks, filter replacements, spark plugs, belt tensioning
Troubleshooting:
Diagnostic procedures for common issues, fault codes (if applicable), drivability problems
Repair:
Step-by-step instructions for component removal, installation, and overhaul
Diagnostics:
Engine performance diagnosis, electrical system troubleshooting, clutch and brake system checks
Specifications:
Torque specifications, clearances, alignments, electrical resistance values
Depth:
Comprehensive, covering from basic maintenance to complete engine and transmission rebuilds, including electrical diagnostics and bodywork.
Configuration:
2.5L (2494 cc) SOHC 12-valve Inline-6
Horsepower:
168 hp @ 5800 rpm (approx.)
Torque:
225 Nm (166 lb-ft) @ 4300 rpm (approx.)
Injection System:
Bosch Motronic ML-1.3 Electronic Fuel Injection
Fuel Type:
Unleaded Premium Gasoline (91+ octane recommended)
Ignition System:
Electronic Ignition, Distributorless Ignition System (DIS) on some later M20s, but typically distributor on 1990 model.
Redline:
Approx. 6500 rpm
Oil Change:
Typically every 7,500 - 10,000 miles (12,000 - 16,000 km) or annually, depending on driving conditions.
Spark Plugs:
Check/replace every 30,000 miles (48,000 km) - refer to manual for specific plug type.
Coolant Flush:
Every 2-3 years or 30,000 - 50,000 miles (48,000 - 80,000 km).
Timing Belt:
M20 engines use a timing belt, typically recommended replacement every 50,000 - 60,000 miles (80,000 - 96,000 km) or 5 years. Crucial to follow manual recommendations to avoid catastrophic engine damage.
Engine Oil:
SAE 15W-40 or 15W-50 API SF or SG (check manual for exact specification).
Engine Oil Capacity:
Approx. 4.25 liters (4.5 US quarts) with filter change.
Coolant:
BMW Blue Antifreeze/Coolant (50/50 mix with distilled water).
Transmission Fluid Manual:
API GL-4 SAE 75W-90 gear oil (e.g., Red Line MT-90).
Transmission Fluid Automatic:
Dexron III (or equivalent, consult manual for exact spec).
Differential Fluid:
API GL-5 SAE 75W-90 gear oil (for standard diff), SAE 75W-140 for LSD.
Brake Fluid:
DOT 3 or DOT 4 brake fluid.
Heater Core:
Common failure point, leading to coolant leaks inside the cabin.
Rubber Bushings:
Age-related degradation of suspension and subframe bushings, affecting handling.
Fuel Pump Relay:
Can fail, preventing the car from starting.
Oil Pan Gasket:
Prone to leaks due to age and material degradation.
Cab Filter:
Non-existent in this model, often a point of discussion for E30 enthusiasts regarding its simplicity.
Bmw Legacy:
BMW's long-standing reputation for building driver-focused, sporty sedans and coupes.
E30 Generation:
The E30 generation (1982-1991) is considered a benchmark for compact sports sedans, with the 325i being a highly sought-after variant.
Transition To E36:
The 1990 model year represents one of the final years of the E30 generation before its successor, the E36, was introduced.
Production Period:
E30 325i produced from 1987 to 1991.
Manufacturing Location:
Germany
