🏷️ Basic Information

Make:

Porsche

Model:

928

Variant Coverage:

928S, 928S2, 928S4, 928GT, 928GTS

Production Years Covered:

1977-1995

Chassis Codes:

928 (early), 928S, 928S2, 928S4, 928GT, 928GTS

👋 Introduction

Segment:

Luxury Grand Tourer (GT)

Original Intent:

Replace the 911 as Porsche's flagship model, offering comfort, performance, and advanced technology.

Competitors:

Ferrari 400/412, Aston Martin V8 Vantage, Jaguar XJ-S, BMW 8 Series (E31).

Design Philosophy:

Front-engine, rear-wheel drive layout, transaxle design for optimal weight distribution.

Technology Introduction:

One of the first production cars with advanced diagnostics, ABS, and a sophisticated engine management system.

Uniqueness:

The only front-engine V8 sports car produced by Porsche.

📋 Manual Details

Technical Coverage:

Comprehensive workshop service and repair

Total Pages:

2600+

Type:

Workshop Service Repair Manual

Primary Language:

English

Digital Format:

Searchable, Printable, Bookmarked iPad-ready PDF

📖 Manual Coverage

Engine:

V8 Engine Mechanical, Fuel System, Ignition System, Cooling System, Lubrication System, Exhaust System, Engine Management (DME/EFI)

Transmission:

Automatic Transaxle (4-speed/5-speed), Manual Transaxle (5-speed), Clutch System, Driveshafts, CV Joints

Chassis And Suspension:

Front Suspension (McPherson Strut), Rear Suspension (Semi-trailing Arm), Power Steering System, Wheel Alignment Specifications

Brakes:

Brake System Hydraulics, ABS (Anti-lock Braking System), Brake Disc and Pad Replacement, Brake Caliper Overhaul

Electrical:

Wiring Diagrams, Lighting System, Starting System, Charging System, Ignition System, Instrumentation, Power Windows, Power Seats, HVAC Controls, Cruise Control, Diagnostic Connectors

Body And Interior:

Body Panels, Doors, Hood, Trunk, Bumpers, Interior Trim, Seats, Safety Belts, HVAC System Components

HVAC:

Air Conditioning System, Heater System, Climate Control

Fuel System:

Fuel Pump, Fuel Injectors, Fuel Pressure Regulator, Fuel Tank, Fuel Lines

Cooling System:

Radiator, Water Pump, Thermostat, Coolant Hoses, Cooling Fan

Lubrication System:

Oil Pump, Oil Filter, Oil Cooler, Oil Pan

Maintenance:

Routine Service Checks, Oil Changes, Filter Replacements, Spark Plug Service, Belt Replacement

Diagnostics:

Troubleshooting Charts, Fault Code Interpretation, Component Testing Procedures

Repair And Rebuild:

Engine Rebuild, Transmission Overhaul, Suspension Component Replacement, Brake System Repair, Electrical Component Repair

Installation:

Component Installation Guidelines, Timing Belt Replacement, Accessory Belt Replacement

Adjustment:

Valve Clearance Adjustment, Idle Speed Adjustment, Parking Brake Adjustment

Depth:

Comprehensive, covering all aspects from basic maintenance to complete engine and transmission rebuilds.

📊 Manual Specifications

File Type:

PDF

Searchability:

Fully searchable text

Printability:

Printable pages

Device Compatibility:

iPad-ready, compatible with most digital devices

Bookmarking:

Internal bookmarks for easy navigation

Quality:

High-resolution digital rendering

Binding:

Digital Download (Not physically bound)

Paper:

Digital (Not applicable to physical print)

⚙️ Engine Specifications

Engine Type:

V8, Naturally Aspirated

Displacement Initial:

4.5 Liters (4474 cc)

Displacement Later Models:

4.7L, 5.0L (928S4/GT/GTS)

Power Early Models:

Approx. 219-234 hp (depending on market and fuel injection)

Power 928S:

Approx. 300-310 hp (Euro spec)

Power 928S4:

Approx. 316 hp @ 5500 rpm

Power 928Gt:

Approx. 326 hp @ 5500 rpm

Power 928Gts:

Approx. 375 hp @ 5500 rpm

Torque 928Gts:

Approx. 398 lb-ft @ 4250 rpm

Injection Type:

Bosch L-Jetronic (early), Bosch KE-Jetronic (later), Bosch Motronic (S4/GT/GTS)

Fuel Type:

Unleaded Gasoline (Premium Octane)

ECU Coverage:

Detailed information on engine control units and their functions.

🔧 Transmission

Transmission Type Early:

4-Speed Automatic Transaxle

Transmission Type Manual:

5-Speed Manual Transaxle (available on many models, standard on 928GT)

Transmission Type Automatic Later:

5-Speed Automatic Transaxle (available on some later models)

Transaxle Design:

Integrated gearbox and differential at the rear axle for 50/50 weight distribution.

Transmission Fluid Spec Auto:

Dexron III (or equivalent)

Transmission Fluid Spec Manual:

GL-4 or GL-5 Gear Oil (SAE 75W-90 or 80W-90)

📐 Dimensions

Length:

Approx. 4680 mm (184.3 in)

Width:

Approx. 1780 mm (70.1 in)

Height:

Approx. 1280 mm (50.4 in)

Wheelbase:

Approx. 2400 mm (94.5 in)

Curb Weight Approx:

1580-1700 kg (3483-3748 lbs) depending on model and options

🛡️ Safety Features

Crash Test Data:

While official ratings are scarce by modern standards, Porsche designed the 928 with significant safety considerations for its era.

ABS:

Anti-lock Braking System (standard on most later models).

Traction Control:

Optional on some later models (e.g., 928GT).

Airbags:

Driver airbag (standard from late 1980s onwards), passenger airbag optional/standard on late models.

Seat Belts:

3-point inertia reel seat belts with pre-tensioners.

Rollover Protection:

Reinforced A-pillars and roof structure.

💡 Technology Features

Audio System:

Integrated Porsche Hi-Fi sound system, often with cassette player and Blaupunkt or Becker head units.

Climate Control:

Automatic climate control with electronic temperature regulation on later models.

Cruise Control:

Standard on most models, electronically controlled.

Diagnostics Port:

Early OBD-I style diagnostic connectors for engine management system.

Advanced Systems:

Integrated diagnostics, ABS, electric seat adjustment, central locking.

🔧 Maintenance

Oil Change:

Every 7,500 miles (12,000 km) or annually, whichever comes first.

Timing Belt:

Every 60,000 miles (96,000 km) or 5 years (critical due to interference engine design).

Spark Plugs:

Every 30,000 miles (48,000 km).

Engine Oil Spec:

SAE 5W-40 or 10W-40 Synthetic (API SJ or higher)

Coolant Spec:

Porsche Approved Antifreeze/Coolant (50/50 mix with distilled water)

Brake Fluid Spec:

DOT 4 (or DOT 5.1 for improved performance)

Common Problems:

Timing belt tensioner failure, fuel distributor leaks, electrical component failures (especially older wiring harnesses), HVAC blower motor, "dreaded" white wires in early models, rear main seal leaks, suspension bushings.

Oil Filter Example:

Mahle OX36D, Mann HU717/1x (check for specific model variant)

Timing Belt Kit Example:

Porsche Part Number 928 105 243 03 (includes belt, tensioner, idler pulleys - always replace as a kit)

📚 Vehicle History

Porsche Philosophy:

Pioneering performance, engineering excellence, and luxury grand touring.

Introduction Year:

1977

Major Updates:

Introduction of the 928S (4.7L V8, improved power), 928S2, 928S4 (5.0L V8, aerodynamic enhancements, ABS), 928GT (performance-focused), and 928GTS (larger displacement 5.4L V8, significant power increase, updated styling).

Design Influences:

Inspired by jet aircraft cockpits and designed for aerodynamic efficiency.

Production Location:

Stuttgart, Germany (Porsche AG)

Production Numbers:

Total production over its lifespan was approximately 61,000 units.

🏆 Awards & Recognition

Safety Award:

Recognized for safety features in its time, though formal NCAP ratings did not exist.

Enthusiast Appreciation:

Consistently praised by automotive journalists and enthusiasts for its engineering and comfort.

Certification:

Manufactured to stringent Porsche quality and performance standards.