Target Audience:
Audi owners, independent repair shops, and DIY enthusiasts seeking professional-grade repair information.
Value Proposition:
Provides dealership-level repair accuracy and detail in a convenient digital format, offering significant savings over professional labor costs.
Accessibility:
Single, easy-to-use PDF manual with searchable content and printable sections.
Accuracy:
Vehicle-specific, not generic, ensuring precise repair instructions.
Engine:
Comprehensive coverage including maintenance, repair, fuel system, emission control, intake, exhaust, cooling, lubrication, ignition, starting, and charging systems.
Drivetrain:
Detailed sections on automatic transmissions, manual transmissions, clutch, transfer cases, propeller shafts, drive shafts, differentials, axles, and suspension components.
Brakes Steering Wheels:
Includes brake control, parking brake, steering column, power steering, tire and wheel specifications.
Body Chassis Electrical:
Coverage extends to body exterior and interior, doors, hood, glass, mirrors, instrument panel, seats, electrical systems, and multiplex/CAN communication.
Comfort Convenience:
Includes air conditioning, supplementary restraint systems (SRS), seat belts, engine immobilizer, cruise control, wiper and washer systems, door locks, meter/audio/visual systems, and horn.
Diagnostic Procedures:
Step-by-step instructions for diagnosing issues across all vehicle systems.
Repair Procedures:
Detailed, vehicle-specific A-Z repair procedures for virtually every component.
Maintenance Procedures:
Comprehensive maintenance tasks and schedules.
Wiring Schematics:
Includes full wiring schematics for electrical systems.
Depth:
Factory-level detail, equivalent to dealership technician manuals; covers complete repair and servicing.
Compatibility:
Windows (Vista 32/64, XP, ME, 98, NT, 2000) and Mac compatible.
Requirements:
Adobe PDF Reader and WinZip (free online).
Printability:
All pages are printable, allowing for enlarged images and selective printing.
Binding:
Digital (PDF format), eliminating physical wear and tear.
Paper Type Equivalent:
N/A (Digital format), but printable on any desired paper type.
Engine Options 1991 Audi 80 90:
Likely includes 2.0L (5-cylinder) and 2.3L (5-cylinder) engines, and potentially a 2.6L V6 in later 90 models. Specific engine codes (e.g., KV, NG, 3B for Coupe Quattro) would be detailed within the manual.
Typical Horsepower Range:
Approximately 110 hp (2.0L) to 130 hp (2.3L), with higher outputs for performance variants like the Audi 90 Quattro Sport.
Fuel Delivery:
Fuel injection systems (e.g., Bosch KE-Jetronic or Motronic) are standard across the range. The manual will cover fuel pump, injectors, pressure regulators, and EFI control modules.
Seat Belts:
Front and rear seat belts, likely with pre-tensioners for front occupants. Manual covers adjustment and replacement.
Supplementary Restraint System:
Driver-side airbag was becoming more common in this era; the manual will detail its function, diagnosis, and replacement if equipped.
Audio System:
Stock stereos were typically AM/FM cassette players. Manual covers removal, installation, and basic wiring for audio components.
Cruise Control:
Cruise control was an available option. The manual will detail its operation, diagnostics, and repair of the actuator and control module.
Multiplex Can Communication:
The inclusion of 'Multiplex/Can Communication' in the coverage list suggests the manual may detail early forms of vehicle network communication or diagnostic data transfer, albeit simpler than modern CAN bus.
Oil Change Interval:
Typically every 5,000-7,500 miles (8,000-12,000 km) or annually, depending on driving conditions. Manual will specify exact intervals based on model and engine.
Timing Belt Interval:
Crucial maintenance item for these engines. Intervals are generally around 60,000 miles (96,000 km) or 4-5 years. Manual will list the exact interval and torque specifications for replacement.
Engine Oil Type:
Likely requires synthetic or semi-synthetic 5W-40 or 10W-40, depending on climate and engine. Manual will provide exact VW/Audi specifications (e.g., VW 500.00).
Coolant Type:
G11 (blue) or G12 (pink/red) antifreeze concentrate mixed with distilled water. Manual will specify the correct type and mixture ratio.
Transmission Fluid Type:
For automatic transmissions, likely a Dexron III or equivalent ATF. For manual transmissions, specific gear oil grades like 75W-90 GL-4 or GL-5. Manual will specify part numbers and types.
Common Wear Items:
Potential for aging rubber components (hoses, bushings), fuel distributor issues on certain injection systems, and electrical connector corrosion.
Electrical System Considerations:
The manual will be invaluable for troubleshooting common electrical gremlins, such as failing relays, sensor issues, and wiring harness degradation over time.
Audi Philosophy:
Audi is known for its engineering prowess, often incorporating advanced technologies like Quattro AWD and five-cylinder engines during this period.
B3 Generation Context:
The 1991 models belong to the Audi 80/90 B3 generation (Typ 89), characterized by its aerodynamic styling and a significant technological leap from its predecessors. The '90' designation typically signified a more powerful engine and better trim levels compared to the '80'.
Manufacturing Region:
Primarily manufactured in Germany.
