🏷️ Basic Information

Make:

BMW

Model:

3 Series / M3

Chassis Code:

E30

Model Year Covered:

1990

Engine Codes Covered:

M20B25, M20B27 (e.g., 325i, 325is, 325e, 325es, M3)

👋 Introduction

Target Audience:

Professional BMW technicians, independent repair shops, and dedicated enthusiasts undertaking complex maintenance and repairs on the E30 platform.

Value Proposition:

Offers definitive, OEM-level information, ensuring accuracy and completeness far beyond generic aftermarket guides. Critical for preserving the integrity and performance of these classic BMWs.

Accuracy:

Vehicle-specific, not generic. Directly from BMW's technical documentation.

Comprehensiveness:

Covers all models and every conceivable repair 'A-Z'.

Diagnostic Tools Reference:

Likely references BMW-specific diagnostic tools and procedures of the era (e.g., basic scan tools, multimeter use).

📋 Manual Details

Primary Coverage:

Comprehensive service and repair procedures for all 1990 BMW 3-Series (E30) and M3 (E30) models.

Estimated Page Count:

Extensive; typically 1000+ pages for complete factory-level documentation.

Type:

Service and Repair Manual

Language:

English

Format:

Likely printed or a high-quality PDF reproduction of the original factory manual.

📖 Manual Coverage

Powertrain:

Engine mechanical, fuel system, ignition system, exhaust system, engine management (DME), cooling system, lubrication system.

Drivetrain:

Manual and automatic transmissions, clutch, driveshafts, differential, axles.

Chassis:

Suspension (front and rear), steering system, braking system (including ABS), wheels and tires.

Electrical:

12V electrical system, battery, charging system, starting system, lighting, instruments and gauges, fuse and relay box, engine control modules, body electrical.

Body:

Body construction, exterior panels, doors, windows, interior trim, HVAC system, body seals.

Maintenance:

Scheduled maintenance intervals, fluid level checks, filter replacements, lubrication.

Troubleshooting:

Diagnostic flowcharts for common drivability, electrical, and mechanical issues.

Repair:

Step-by-step repair procedures for all major components and systems, including engine rebuild, transmission overhaul, brake caliper replacement, suspension component renewal.

Diagnostics:

Engine diagnostics (e.g., checking sensor readings via DME), electrical system testing, pressure testing.

Specifications:

Torque specifications, clearances, fluid capacities, electrical resistance values, diagnostic trouble codes (DTCs).

Depth:

Factory-level detail, suitable for professional technicians and advanced DIY enthusiasts. Covers complete overhauls, component-level diagnostics, and calibration procedures.

📊 Manual Specifications

Digital Format Considerations:

Searchable text, high-resolution diagrams, printable pages. Original factory manuals are often scanned, so quality can vary but is generally excellent for understanding procedures.

Print Quality Considerations:

Paper type is typically durable, designed for workshop environments. Diagrams are clear and legible.

Binding Type Considerations:

Originals often coil-bound or perfect-bound for durability. Recreations may vary.

Paper Type Considerations:

Often on a matte finish paper to reduce glare in workshop lighting.

⚙️ Engine Specifications

Engine Options E30 1990:

M20 inline-six cylinder, 2.5L (152 cu in) for 325i/is, and potentially the M20 inline-six, 2.7L (164 cu in) for earlier 325e/es models still in service.

325I Horsepower:

Approximately 168-171 hp (SAE net) depending on market and specific configuration.

325I Torque:

Approximately 215 Nm (159 lb-ft) at 4750 rpm for the 2.5L M20.

M3 E30 Engine:

S14 inline-four cylinder, 2.3L (140 cu in). High-revving, DOHC, 16-valve engine derived from the M10 block with a unique DOHC head.

M3 E30 Horsepower:

Approximately 192-200 hp (SAE net) for standard Euro/US spec models.

M3 E30 Torque:

Approximately 230-240 Nm (170-177 lb-ft) at 4750 rpm for the 2.3L S14.

Fuel Injection:

Bosch Motronic electronic fuel injection (EFI).

Fuel Type:

Unleaded gasoline (premium octane recommended).

Timing Belt M20:

Recommended replacement every 30,000-40,000 miles or 3-4 years. Critical for preventing catastrophic engine damage.

Valve Adjustment S14:

Requires periodic valve lash adjustment (shimming) due to the S14's valvetrain design.

🔧 Transmission

Standard Transmission Type:

Getrag 260 5-speed manual transmission.

Optional Transmission Type:

ZF 4HP22 4-speed automatic transmission.

Transmission Fluid Spec:

Manual: BMW MTF LT-2 or equivalent. Automatic: ATF Dexron II or III.

Clutch Type:

Hydraulically actuated single dry plate clutch.

📐 Dimensions

Wheelbase E30:

Approx. 2568 mm (101.1 inches).

Length E30:

Approx. 4340 mm (170.9 inches) for Sedan/Coupe, slightly different for Convertible.

Width E30:

Approx. 1675 mm (65.9 inches).

Height E30:

Approx. 1380 mm (54.3 inches).

Curb Weight E30 325I:

Approx. 1350-1400 kg (2976-3086 lbs).

Curb Weight M3 E30:

Approx. 1200-1260 kg (2646-2778 lbs).

Wheel Bolt Pattern:

5x120 mm.

Wheel Offset:

Typically ET12 to ET20 depending on wheel size and model.

🛡️ Safety Features

Crash Testing Era:

Safety standards of the late 1980s; E30s feature a reinforced passenger cell, crumple zones, and safety glass.

ABS:

Anti-lock Braking System (ABS) was optional on most 3-Series models and standard on the M3.

Seatbelts:

Three-point inertia-reel seatbelts front and rear.

Steering Column:

Collapsible steering column.

Fuel Tank Placement:

Safely positioned in the rear of the vehicle.

💡 Technology Features

Audio System:

Factory cassette player with optional CD changer integration. Basic AM/FM radio.

Climate Control:

Manual or optional automatic climate control (often referred to as 'Air Conditioning' or 'Heated Climate Control').

ABS Availability:

Anti-lock Braking System (ABS) was a key electronic driver assistance feature.

Connectivity Era:

Limited by modern standards; no integrated Bluetooth or USB ports from the factory.

🔧 Maintenance

Oil Change Interval:

Typically 5,000-7,500 miles or annually, using synthetic or high-quality conventional oil.

Spark Plug Replacement:

Bosch W8AC or equivalent, recommended replacement every 15,000-20,000 miles.

Brake Fluid Flush:

Every 2 years, using DOT 4 brake fluid.

Engine Oil Capacity 2.5L:

Approx. 4.5 liters (4.8 US quarts) with filter change.

Engine Oil Type:

BMW recommends 5W-30 or 10W-40 (API SG or higher, or BMW LL-98 specification equivalent for the era).

Coolant Type:

BMW Blue Antifreeze or equivalent ethylene glycol based coolant mixed 50/50 with distilled water.

Power Steering Fluid:

ATF Dexron II or III.

Common E30 Issues:

Cooling system leaks (cracked expansion tank, hoses), fuel distributor diaphragm leaks (M20), perished rubber bushings (control arms, subframes), fuel pump failure, instrument cluster illumination/sender issues, rear subframe mounting cracks (especially M3), sunroof drain blockage.

M3 E30 Specific Issues:

Rear subframe mounts fatigue/crack, oil starvation under extreme G-forces (pre-oil cooler models), specific S14 engine component wear.

📚 Vehicle History

Bmw Legacy:

BMW's reputation for building sporty, driver-focused sedans and coupes, continuing the legacy of models like the 02 Series.

E30 Introduction:

The E30 generation replaced the E21 3 Series and was produced from 1982 to 1994, with the 1990 model year being towards the latter end of its lifecycle, benefiting from evolutionary improvements.

E30 M3 Significance:

The E30 M3, introduced in 1986, was homologated for motorsport and is considered one of the most iconic performance cars of its era, distinguished by its flared fenders and unique body panels.

Production Period:

1982-1994 (E30 Generation). 1990 models are part of the significant mid-to-late production run.

🏆 Awards & Recognition

E30 Market Perception:

Widely recognized by automotive journalists and enthusiasts as a benchmark sports sedan/coupe of its era, lauded for its driving dynamics.

M3 E30 Awards:

The E30 M3 is frequently cited in 'best cars' lists, celebrated for its racing pedigree and exceptional handling. It competed successfully in touring car championships worldwide.