📚 Vehicle Manual Information

Audi 90 1988 1989 1990 1991 92 Factory Service Repair Manual

🏷️ Basic Information

Make:

Audi

Model:

90

Model Code:

Type 85

Production Years Covered:

1988, 1989, 1990, 1991, 1992

👋 Introduction

Vehicle Class:

Compact Executive Sedan/Wagon

Target Audience:

Enthusiasts, DIY mechanics, independent repair shops specializing in European vehicles.

Competitors Late 80S:

BMW 3 Series (E30), Mercedes-Benz 190E (W201), Volvo 240, Acura Integra, Toyota Camry.

Design Philosophy:

Sporty handling, refined interior, Quattro all-wheel drive option, sophisticated engineering for its era.

Value Proposition:

Provides detailed, factory-accurate information essential for maintaining and repairing the Audi 90, saving significant costs compared to dealership service.

📋 Manual Details

Manual Type:

Factory Service Repair Manual

Language:

English

Format:

Digital (likely PDF)

📖 Manual Coverage

Engine Mechanical:

Complete engine overhaul, component diagnostics, timing belt replacement, piston and ring installation, cylinder head repair, valve train service, lubrication system, cooling system.

Engine Electrical:

Ignition system, fuel injection system (CIS-E/Motronic), starting system, charging system, engine control unit (ECU) diagnostics, sensor and actuator testing, wiring diagrams.

Transmission Manual:

Clutch system, gearbox overhaul, shift linkage adjustment, differential service, fluid specifications and replacement.

Transmission Automatic:

Transmission overhaul, torque converter service, hydraulic control systems, electronic control unit (TCU) diagnostics, fluid replacement and adjustment.

Suspension And Steering:

Front and rear suspension component replacement, shock absorber and strut service, ball joint and tie rod end replacement, power steering system service, wheel alignment specifications.

Brakes:

Front and rear brake system (disc brakes), ABS (Anti-lock Braking System) diagnostics and repair, brake fluid replacement, caliper and rotor service, parking brake adjustment.

Electrical System:

Lighting systems (headlights, taillights, interior), power windows, central locking, horn, wiper system, fuse and relay identification and testing, wiring diagrams for all vehicle systems.

Body And Chassis:

Body panel repair and replacement, door mechanisms, hood and trunk operation, bumper systems, interior trim removal and installation, rust prevention and repair.

HVAC:

Heating, ventilation, and air conditioning (HVAC) system diagnostics, refrigerant handling, component replacement (compressor, condenser, evaporator), blower motor service.

Maintenance:

Routine maintenance schedules, oil and filter changes, spark plug replacement, air filter replacement, coolant flushes, brake fluid changes, fuel filter replacement.

Troubleshooting:

Diagnostic flowcharts for common drivability issues, electrical system faults, starting problems, and performance issues.

Repair:

Step-by-step repair instructions for all major vehicle systems, including component removal, installation, and adjustment.

Diagnostics:

Detailed diagnostic procedures using specifications, test procedures for sensors, actuators, and control modules.

Depth Level:

Comprehensive (from basic maintenance to full engine/transmission rebuilds and complex electrical diagnostics).

📊 Manual Specifications

Digital Format:

PDF (Portable Document Format), likely with searchable text.

Image Resolution:

High-resolution scans for clear diagrams, illustrations, and text.

Binding:

N/A (Digital Format)

Paper Quality:

N/A (Digital Format)

Manual Completeness:

Full factory service manual, covering all aspects of repair and maintenance for the specified model years.

⚙️ Engine Specifications

Engine Code Common:

NG (2.3L 5-cylinder)

Engine Type:

Inline 5-cylinder, naturally aspirated

Displacement:

2309 cc (2.3 Liters)

Horsepower Peak:

130 hp @ 5500 rpm (for NG engine)

Torque Peak:

145 lb-ft @ 3000 rpm (for NG engine)

Fuel Delivery:

Bosch CIS-E (Continuous Injection System - Electronic) or Motronic electronic fuel injection, depending on model year and market.

Fuel Type:

Unleaded Gasoline

Coolant Type:

Ethylene Glycol based coolant (e.g., G11 specification).

Oil Type:

API SG/SH, SAE 5W-30 or 5W-40 (check manual for specific recommendations).

🔧 Transmission

Transmission Type Standard:

5-speed Manual Transmission

Transmission Type Optional:

ZF 4-speed Automatic Transmission

Drivetrain:

Front-Wheel Drive (FWD) or Quattro All-Wheel Drive (AWD)

Manual Transmission Fluid:

API GL-4, SAE 75W-90 synthetic gear oil.

Automatic Transmission Fluid:

ATF Dexron II or equivalent.

📐 Dimensions

Wheelbase:

Approx. 2600 mm (102.4 in)

Length:

Approx. 4400 mm (173.2 in)

Width:

Approx. 1700 mm (66.9 in)

Height:

Approx. 1380 mm (54.3 in)

Curb Weight FWD:

Approx. 1250 kg (2756 lbs)

Curb Weight Quattro:

Approx. 1350 kg (2976 lbs)

Gross Vehicle Weight Rating:

Varies by configuration, refer to vehicle data plate.

🛡️ Safety Features

NHTSA Ratings:

Data for this era is less standardized. Generally considered safe for its time. (Specific ratings may not be readily available).

ABS:

Available (standard on many Quattro models, optional on FWD).

Airbags:

Driver airbag standard from 1990/1991 onwards. Passenger airbag optional or unavailable.

Seatbelts:

3-point inertia-reel seatbelts front and rear.

Quattro AWD Benefit:

Enhanced traction and stability, particularly in adverse weather conditions.

💡 Technology Features

Audio System:

Factory AM/FM cassette stereo with optional CD player. Premium sound systems available.

Dashboard Features:

Analog gauges, driver information display (basic functions like outside temp, fuel economy).

ABS System:

Bosch Anti-lock Braking System (ABS) on select models.

Early Electronics:

Central locking, power windows, power mirrors, cruise control (optional).

🔧 Maintenance

Oil Change Interval:

Every 5,000-7,500 miles or 6-12 months, whichever comes first (synthetic oil recommended).

Timing Belt Replacement:

Every 60,000 miles or 5 years (critical component, failure can cause catastrophic engine damage).

Spark Plug Replacement:

Every 30,000 miles (standard plugs) or 60,000 miles (platinum plugs).

Coolant Flush Interval:

Every 2 years or 30,000 miles.

Power Steering Fluid:

Pentosin CHF 11S or equivalent hydraulic fluid.

Brake Fluid Type:

DOT 3 or DOT 4.

Common Problems:

Worn suspension bushings, aging electrical connectors and wiring harnesses, fuel distributor leaks (CIS-E), weak fuel pumps, cracked dashboard material, seized sunroof mechanisms, door seal degradation.

Engine Mounts:

Hydraulic engine mounts can degrade over time, leading to vibration.

Odometer Gears:

Plastic odometer gears in the instrument cluster are prone to breaking.

📚 Vehicle History

Audi Legacy:

Known for engineering excellence, quattro all-wheel drive technology, and a focus on premium quality.

Predecessor:

Audi 80/Fox

Successor:

Audi A4 (B5 platform)

Platform:

VW Group B3 platform (shared with Audi 80/89 and Volkswagen Passat B3).

Manufacturing Location:

Ingolstadt, Germany; also some production in the USA (Paulsboro, NJ).

🏆 Awards & Recognition

Automotive Press Reviews:

Generally well-received for its driving dynamics, build quality, and the availability of Quattro. Often praised for its comfortable ride and refined interior compared to some competitors.