Segment:
Compact Executive Sports Sedan/Coupe
Target Audience:
Enthusiasts, DIY mechanics, owners seeking to maintain and repair their classic BMW.
Key Competitors:
Mercedes-Benz 190E, Audi 80/90, Ford Sierra XR4i, Alfa Romeo 75.
Vehicle Reputation:
Renowned for its sporty handling, balanced chassis, and driver engagement, defining the modern BMW driving experience.
Manual Value Proposition:
Essential resource for preserving and maintaining the performance and longevity of the E30 325i/325is.
Engine:
Comprehensive coverage of the M20B25 inline-six engine, including diagnostics, repair, and overhaul.
Fuel System:
Detailed information on Bosch Motronic fuel injection system, fuel pump, injectors, fuel lines, and pressure regulation.
Ignition System:
Coverage of the electronic ignition system, coil, distributor, spark plugs, and timing.
Cooling System:
Radiator, water pump, thermostat, coolant hoses, and fan assembly maintenance and repair.
Exhaust System:
Catalytic converter, muffler, exhaust manifold, and pipes diagnosis and replacement.
Transmission Manual:
Repair and overhaul procedures for the Getrag 260 5-speed manual transmission. Clutch system diagnosis and replacement.
Transmission Automatic:
Information on the ZF 4HP22 4-speed automatic transmission, including fluid changes and basic troubleshooting.
Drivetrain:
Driveshaft, CV joints, differential, and axle shaft service and repair.
Suspension Front:
MacPherson struts, control arms, ball joints, bushings, and anti-roll bar service.
Suspension Rear:
Trailing arms, shock absorbers, bushings, and spring replacement.
Steering System:
Power steering pump, rack and pinion, steering linkage, and wheel alignment procedures.
Brakes Front:
Disc brake rotor, caliper, pads, and brake line service. ABS system components if applicable.
Brakes Rear:
Drum brake (on some models) or disc brake caliper, pads, and parking brake mechanism.
Electrical System:
Wiring diagrams, fuse box layout, battery, alternator, starter, lighting, and accessories.
Body And Frame:
Panel removal and installation, body repair, door mechanisms, and interior trim.
HVAC:
Heater core, blower motor, A/C system components, and climate control adjustments.
Troubleshooting:
Diagnostic charts and procedures for common problems.
Routine Maintenance:
Oil changes, filter replacements, spark plug replacement, fluid checks, belt inspections.
Engine Repair:
Cylinder head removal/installation, piston and connecting rod service, crankshaft bearing replacement, timing chain/belt replacement.
Fuel System Service:
Fuel injector cleaning, fuel pump replacement, fuel pressure testing.
Transmission Overhaul:
Detailed steps for disassembling, inspecting, and reassembling manual and automatic transmissions.
Brake System Repair:
Brake pad/shoe replacement, caliper/wheel cylinder overhaul, brake line bleeding, ABS component replacement.
Suspension Replacement:
Strut, shock absorber, control arm, bushing, and ball joint replacement.
Electrical Diagnostics:
Using multimeters and oscilloscopes to diagnose electrical faults, starter/alternator testing.
Body Panel Replacement:
Procedures for replacing fenders, doors, hoods, and trunk lids.
Climate Control Repair:
Recharging A/C systems (with proper certification), replacing heater cores and blower motors.
Depth:
Extremely high. Covers everything from basic fluid changes to complete engine and transmission rebuilds.
Diagnostic Level:
Advanced diagnostics for mechanical, electrical, and fuel injection systems.
Special Tools:
Lists required special tools for specific repair procedures.
Oil Change Interval:
Typically every 5,000 - 7,500 miles or 6-12 months, whichever comes first, depending on driving conditions.
Air Filter Replacement:
Inspect every 15,000 miles, replace as needed or every 30,000 miles.
Spark Plug Replacement:
Typically every 30,000 - 60,000 miles with platinum or iridium plugs (copper plugs require more frequent replacement).
Coolant Flush:
Every 2-3 years or 30,000-50,000 miles.
Timing Belt Replacement:
Crucial! M20 engines use a timing belt. Replace every 50,000-60,000 miles or 5 years to prevent catastrophic engine damage due to interference design.
Engine Oil:
10W-40 or 20W-50 synthetic or semi-synthetic oil recommended. Check owner's manual for precise specifications.
Engine Oil Capacity:
Approx. 4.5 Liters (4.7 Quarts) with filter.
Brake Fluid:
DOT 3 or DOT 4 (check manual for specific recommendation).
Engine Mounts:
Commonly degrade over time, leading to vibration.
Coolant Leaks:
Plastic coolant expansion tanks can crack; check hoses and thermostat housing for leaks.
Window Regulators:
Manual and electric window regulators can fail.
Fuel Pump Reliability:
In-tank fuel pumps can become noisy or fail over time.
Rust:
Common E30 issue, particularly around wheel arches, rocker panels, and jacking points. Regular inspection is crucial.
Dashboard Cracks:
The vinyl dashboards are prone to cracking from sun exposure.
Idle Control Valve:
Can become clogged, leading to rough idling or stalling.
Bmw Philosophy:
Continued BMW's legacy of producing driver-focused, performance-oriented luxury vehicles.
E30 Introduction:
The E30 generation succeeded the E21 3 Series and introduced significant advancements in chassis design and engineering.
325I Introduction:
The 325i, powered by the M20B25 engine, replaced the 323i and 325e, offering a significant performance upgrade.
325Is Distinction:
The 'is' designation often referred to sportier variants, potentially with specific suspension tuning or aerodynamic enhancements (depending on market).
Production Years:
1982-1994 (E30 generation globally), 1984-1990 (for 325i/325is models covered by this manual).
Manufacturing Locations:
Germany, South Africa, USA (CKD assembly)
