Positioning:
The Audi 90 was Audi's premium compact executive sedan, positioned to compete with European and Japanese luxury marques, offering advanced technology and refined styling.
Competitors:
BMW 3 Series, Mercedes-Benz 190E, Acura Legend, Lexus ES 250
Audi Heritage:
Known for its Quattro all-wheel-drive system (optional on some models), sophisticated engineering, and emphasis on driver engagement.
Target Audience:
DIY enthusiasts, independent repair shops, and Audi owners seeking to maintain their vehicles with dealer-level accuracy.
Primary Coverage:
Factory Service Workshop Manual
Secondary Coverage:
Repair, Maintenance, Diagnostics, Troubleshooting
Estimated Page Count:
Extensive (typical factory manuals for this era exceed 1000 pages across multiple volumes or sections)
Type:
Factory Service Manual
Compatibility:
Windows 95/98/ME/XP (indicating it may be an older digital conversion)
Powertrain:
Engine (all variants), Fuel System, Exhaust System, Ignition System, Cooling System, Lubrication System
Drivetrain:
Transmission (manual & automatic), Clutch, Drive Axles, Differential, Quattro All-Wheel Drive System
Chassis:
Suspension (front & rear), Steering System, Brakes (hydraulic, ABS), Wheels & Tires
Electrical:
12V Electrical System, Battery, Charging System, Ignition System, Lighting, Gauges & Instruments, Wipers & Washers, Power Accessories, Audio System Wiring, Engine Control Unit (ECU) & Sensors, Anti-lock Braking System (ABS) Electronics
Body:
Body Structure, Exterior Panels, Doors, Hood, Trunk Lid, Bumpers, Glass, Interior Trim, Seats, HVAC System, Body Sealing
Routine Maintenance:
Oil Change, Filter Replacement, Spark Plug Replacement, Air Filter Replacement, Coolant Flush, Brake Fluid Flush, Drive Belt Inspection/Replacement, Wiper Blade Replacement
Major Repairs:
Engine Rebuild, Transmission Overhaul, Clutch Replacement, Brake System Overhaul, Suspension Component Replacement, Steering Rack Replacement, Radiator Replacement, Starter Motor/Alternator Replacement
Diagnostics:
Troubleshooting Flowcharts, Fault Code Interpretation (OBD-I for some models), Component Testing Procedures, Wiring Diagrams for Diagnosis
Technical Data:
Specifications, Tolerances, Torque Values, Alignment Specs, Fluid Capacities & Types, Electrical Schematics
Depth:
Comprehensive, covering everything from basic adjustments to complete component rebuilds, mirroring dealer technician procedures.
Engine Displacement Liter:
2.3 L
Engine Configuration:
Inline 5-cylinder (different variants existed across the model run, including 10-valve and 20-valve, naturally aspirated)
Engine Code Examples:
NG, AAR (need to verify specific codes for 88-92 model range)
Horsepower Range:
Approximately 130-170 hp (depending on engine variant and emissions compliance)
Torque Range:
Approximately 145-160 lb-ft
Fuel Delivery:
Bosch KE-Jetronic (CIS-E) or later Motronic fuel injection systems
Fuel Type:
Unleaded Gasoline
Transmission Type Standard:
5-speed Manual Transaxle
Transmission Type Optional:
4-speed Automatic Transaxle
Drivetrain Options:
Front-Wheel Drive (FWD) and Audi's legendary Quattro All-Wheel Drive (AWD)
Fluid Type Manual:
API GL-4 Gear Oil (e.g., SAE 75W-90 or 80W-90, specific viscosity may vary by temperature)
Fluid Type Automatic:
ATF Dexron II/III or equivalent
NHTSA Ratings:
N/A (pre-dates widespread standardized testing as we know it today)
ABS:
Anti-lock Braking System (ABS) available/standard on certain trims/years
Quattro:
Quattro AWD system provides enhanced traction and stability
Airbags:
Driver-side airbag typically standard from mid-cycle onward; passenger airbag less common or optional.
Seat Belts:
3-point front and rear seat belts
Audio System:
Factory cassette player with AM/FM radio, optional CD player available on later models. Amplified sound systems were common.
ABS:
Standard or optional ABS system for enhanced braking control.
Original Connectivity:
Limited to analog systems; no modern Bluetooth or USB connectivity from the factory.
HVAC System:
Manual or Automatic Climate Control (ECC - Electronic Climate Control on higher trims), effective but can suffer from aged components like blower motors and evaporator cores.
Oil Change Interval Miles:
Typically 3,000-7,500 miles (dependent on oil type and driving conditions, consult specific vehicle maintenance schedule within the manual)
Timing Belt Replacement Miles:
Approximately 60,000 miles (critical for 5-cylinder engines; failure causes catastrophic damage)
Spark Plug Replacement Miles:
Varies by plug type, often 30,000-60,000 miles
Engine Oil Viscosity:
Commonly 5W-40 or 10W-40 synthetic blend/full synthetic (refer to manual for exact spec based on temperature and engine condition)
Coolant Type:
G11 (blue/green) ethylene glycol based coolant, mixed 50/50 with distilled water
Brake Fluid Type:
DOT 3 or DOT 4
Common Electrical:
Corrosion in connectors, failing fuel pump relays, aged wiring insulation, instrument cluster issues.
Common Mechanical:
Timing belt failure risk (if not replaced on schedule), CV joint wear, suspension bushing degradation, heater core leaks, exhaust manifold cracks (on some 5-cyl models).
Common Fuel System:
Clogged fuel injectors (especially on CIS-E systems), failing fuel pressure regulators, aging fuel lines.
Audi Legacy:
Audi's reputation for engineering, durability, and its pioneering Quattro all-wheel-drive system.
Generation Details:
The Audi 90 (Type 85/8C) was a sportier, more luxurious version of the Audi 80, often featuring the 5-cylinder engine and Quattro. It was replaced by the Audi A4.
Manufacturing Location:
Germany
Key Market Introduction:
North America (significant presence), Europe
Automotive Journal Reviews:
Consistently praised for its handling (especially Quattro models), build quality, and the unique character of the 5-cylinder engine. Competed well against German rivals.
Reliability Perception:
Generally good reliability, but requires diligent maintenance due to its European engineering complexity.
