1988 BMW 528e Repair Manual

The 1988 BMW 528e is a luxury executive sedan featuring the M20B27 2.7L inline-6 "Eta" engine with 121 horsepower, rear-wheel drive, 5-speed manual or 4-speed automatic transmission, advanced suspension system, and comprehensive electronic systems. This repair manual covers essential maintenance, troubleshooting, and repair procedures for the entire vehicle. Below are key sections for specifications, maintenance schedules, engine repair, electrical systems, suspension, brakes, and troubleshooting.

Vehicle Specifications

Key technical data for the 1988 BMW 528e E28 model.

Specification	Details
Engine	M20B27 2.7L inline-6 Eta engine
Power Output	121 hp @ 4250 rpm
Torque	170 lb-ft @ 3250 rpm
Transmission	5-speed manual or 4-speed automatic
Fuel System	Bosch L-Jetronic fuel injection
Fuel Type	Premium unleaded (91 octane)
Brakes	Front disc, rear disc with ABS
Suspension	Independent front and rear
Curb Weight	Approximately 2,900 lbs
Fuel Capacity	16.4 gallons

Maintenance Schedule

Regular maintenance intervals for optimal performance and longevity.

1. Oil and filter change: Every 7,500 miles or 12 months
2. Spark plugs: Replace every 30,000 miles
3. Air filter: Inspect every 15,000 miles, replace as needed
4. Coolant flush: Every 2 years or 30,000 miles
5. Brake fluid: Replace every 2 years
6. Timing belt: Replace every 60,000 miles
7. Transmission fluid: Every 30,000 miles (automatic)

WARNING! Always use BMW-approved fluids and follow torque specifications precisely.

Engine Systems

Comprehensive engine repair and maintenance procedures.

1. Engine removal: Disconnect battery, drain fluids, remove accessories
2. Cylinder head: Torque sequence critical - 22 ft-lbs + 90° turn
3. Valve adjustment: Cold engine - 0.010" intake, 0.012" exhaust
4. Fuel injection: Test fuel pressure (36-40 psi), inspect injectors
5. Ignition system: Check coil resistance, rotor, distributor cap
6. Emission controls: Inspect vacuum lines, check oxygen sensor

CAUTION! Engine components are precision parts; handle with care and use proper tools.

Transmission & Drivetrain

• Manual Transmission: Getrag 260/5, fluid capacity 1.2L
• Automatic Transmission: ZF 4HP22, fluid capacity 3.0L
• Clutch: Hydraulic system, pedal free play 0.2-0.4 inches
• Differential: Final drive ratio 2.93:1, fluid capacity 1.0L
• Drive Shaft: Two-piece with center support bearing
• U-Joints: Lubricate every 30,000 miles

Electrical Systems

Wiring diagrams and electrical component service procedures.

Battery: 12V 65Ah, located in trunk, positive ground

Charging System: Alternator output 80A, voltage regulator integral

Lighting: Headlight adjustment, bulb replacement procedures

Instrument Cluster: SI board battery replacement, speedometer calibration

Power Windows: Regulator replacement, motor testing procedures

Central Locking: Vacuum system diagnosis and repair

Suspension & Steering

Front and rear suspension overhaul and alignment procedures.

1. Front strut replacement: Remove wheel, brake line, and mounting bolts
2. Control arms: Check bushings and ball joints for wear
3. Rear suspension: Semi-trailing arm design, check subframe mounts
4. Steering gear: Recirculating ball type, adjustment procedures
5. Wheel alignment: Front toe 0°±0.2°, camber -0.5°±0.5°

Tip: Always replace suspension components in pairs and perform alignment after service.

Brake Systems

Hydraulic brake system service and ABS maintenance.

1. Brake pad replacement: Front and rear specifications differ
2. Rotor machining: Minimum thickness specifications provided
3. Brake bleeding: Sequence - RR, LR, RF, LF
4. ABS diagnosis: Test wheel sensors (850-1200 ohms)
5. Parking brake: Cable adjustment at rear calipers
6. Master cylinder: Bench bleeding procedure

WARNING! Brake system is critical for safety; test thoroughly after service.

Fuel System

Fuel delivery and injection system service procedures.

Fuel Pump: In-tank and main pump, test pressure and flow rate

Fuel Filter: Replace every 15,000 miles, located under vehicle

Injectors: Flow test and cleaning procedures

Cold Start Valve: Function test and replacement

Fuel Tank: Removal and cleaning procedures

CAUTION! Relieve fuel pressure before disconnecting any fuel lines.

Cooling System

Radiator, thermostat, and water pump service procedures.

1. Radiator replacement: Drain coolant, remove hoses and mounting
2. Thermostat: 80°C opening temperature, housing gasket replacement
3. Water pump: Plastic impeller type, inspect for wear
4. Coolant: BMW-approved blue coolant, 50/50 mix with distilled water
5. Electric fan: Temperature switch testing and replacement

Interior & Body

Interior trim, dashboard, and body panel repair procedures.

Component	Service Procedure
Dashboard	Removal for instrument cluster service
Seats	Power seat motor and gear replacement
Door Panels	Clip locations and removal sequence
Carpet	Removal for floor pan inspection
Sunroof	Manual and power sunroof adjustment

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Hard starting	Fuel pressure, ignition timing	Test fuel pressure, check reference sensors
Overheating	Thermostat, water pump, air in system	Bleed cooling system, test thermostat
Poor idle	Vacuum leaks, ICV malfunction	Smoke test for leaks, clean idle control valve
Brake pulsation	Warped rotors, stuck calipers	Measure rotor runout, lubricate slide pins
Electrical issues	Ground connections, battery	Clean trunk and engine grounds, load test battery

Reset: Disconnect battery for 10 minutes to reset adaptations.

Service: Contact BMW dealership or certified technician for complex issues.