Positioning:
The Audi 100 (C4) represented Audi's mid-size luxury offering, positioned against competitors like the BMW 5 Series and Mercedes-Benz E-Class. It emphasized comfort, refined engineering, and a premium interior.
Competitors:
BMW 5 Series (E34), Mercedes-Benz E-Class (W124), Volvo 960, Saab 9000.
Vehicle Features:
Standard Quattro all-wheel drive (on many models), refined V6 engines, spacious and well-appointed interior, comfortable ride quality, advanced (for its time) safety features.
Value:
Provides DIY enthusiasts and independent repair shops with the necessary technical data to service, maintain, and repair the Audi 100 C4, saving on dealership costs and ensuring proper upkeep.
Primary Coverage:
North American Market (implied by common sales focus, but manual itself may be international)
Engine Variants Covered:
Likely covers 2.8L V6 (AAF, ABC engine codes), and potentially 2.6L V6 (ABC engine code) if offered in specific 1994 markets. Turbocharged 2.2L 20V (RR engine code) from the S4 variant might also be included.
Body Styles Covered:
Sedan (4-door), Avant (Wagon)
Estimated Page Count:
500-1000+ (typical for comprehensive workshop manuals)
Type:
Workshop Service and Repair Manual
Engine Mechanical:
Engine overhaul, cylinder head, valve train, pistons, crankshaft, connecting rods, lubrication system, cooling system, timing belt/chain.
Engine Performance:
Fuel injection system, ignition system, exhaust system, emissions control.
Transmission Manual:
Manual gearbox repair, clutch system, driveline components.
Transmission Automatic:
Automatic transmission repair and overhaul (likely ZF or Audi's own design), torque converter, transmission control.
Brakes:
Brake system diagnosis, repair, components (calipers, rotors, master cylinder, ABS).
Suspension:
Front and rear suspension components, shock absorbers, springs, bushings, wheel alignment.
Steering:
Power steering system, steering rack, tie rods.
Electrical System:
Wiring diagrams, charging system (alternator, battery), starting system, lighting, instruments, gauges, power windows, mirrors, central locking.
HVAC:
Heating, ventilation, and air conditioning system diagnosis and repair.
Body And Interior:
Body panel removal/installation, interior trim, door mechanisms, seat adjustments, glass replacement.
Diagnostics:
Troubleshooting charts, diagnostic codes, OBD-I information (if applicable).
Preventative Maintenance:
Oil changes, filter replacements, spark plug replacement, fluid checks, belt inspections.
Routine Repairs:
Brake pad replacement, exhaust system repair, suspension component replacement.
Major Repairs:
Engine rebuilds, transmission overhauls, cylinder head gasket replacement.
Troubleshooting:
Systematic diagnosis of common and uncommon faults.
Diagnostics:
Guidance on using diagnostic tools and interpreting fault codes.
Wiring Diagrams:
Detailed electrical schematics for all vehicle systems.
Depth:
Comprehensive: Covers everything from basic maintenance to complete engine and transmission rebuilds, including detailed electrical schematics and diagnostic procedures.
Engine Code:
AAF (2.8L V6 12V)
Engine Type:
Naturally Aspirated V6
Displacement:
2.8 liters (2771 cc)
Bore X Stroke:
82.5 mm x 91.3 mm
Compression Ratio:
10.3:1
Horsepower:
172 hp @ 5500 rpm (approx.)
Torque:
184 lb-ft @ 3000 rpm (approx.)
Engine Codes Other:
ABC (2.6L V6 12V), RR (2.2L 20V Turbocharged - S4 model)
Injection Type:
Multi-point Fuel Injection (MPI) - Bosch Motronic
Fuel Type:
Unleaded Gasoline (91 Octane or higher recommended)
Timing Belt:
Yes, belt driven. Replacement interval typically 60,000-90,000 miles or 5-7 years.
Transmission Type:
5-speed Manual Transmission (e.g., KXS, FKA)
Transmission Type:
4-speed Automatic Transmission (e.g., 097, 098)
Drivetrain:
Front-wheel drive (FWD) standard on some models, Quattro all-wheel drive (AWD) optional or standard on higher trims/performance variants.
Manual Transmission Fluid:
API GL-4, SAE 75W-90 synthetic gear oil (check specific manual for exact spec, e.g., G 052 171 A2).
Automatic Transmission Fluid:
G 002 000 or equivalent ATF (e.g., Dexron III). Check specific manual for exact Audi specification.
Length:
Approx. 481 cm (Sedan), 479 cm (Avant)
Height:
Approx. 143 cm (Sedan), 145 cm (Avant)
Wheelbase:
Approx. 270 cm
Curb Weight:
Approx. 1500-1700 kg, depending on engine and drivetrain
Gross Vehicle Weight Rating:
Varies by model, typically around 2100-2300 kg
Cargo Volume Sedan:
Approx. 16.5 cubic feet (sedan)
Cargo Volume Avant:
Approx. 22.0 cubic feet (rear seats up), 55.0 cubic feet (rear seats folded)
NHTSA Ratings:
Specific ratings for 1994 models may vary by market and may not be readily available. Generally, vehicles of this era were not subjected to the same rigorous testing protocols as today.
ABS:
Standard on most models, often Bosch ABS system.
Quattro AWD:
Standard or optional, significantly enhances traction and stability.
Airbags:
Driver and passenger airbags standard on many models.
Seatbelts:
3-point inertia-reel seatbelts with pretensioners.
Body Structure:
Integrated safety cage, crumple zones.
Audio System:
Audi Gamma or Symphony cassette/radio systems, often with optional CD changer. Sound quality was a strong point for the era.
Climate Control:
Manual or optional automatic climate control (Climatronic) with integrated diagnostic functions.
Cruise Control:
Available on most models.
Traction Control:
ASR (Anti-Slip Regulation) available on some models, often linked with ABS.
Connectivity Features:
Limited by era. No integrated Bluetooth or smartphone mirroring. Optional CD changer connectivity.
Oil Change Interval:
Every 5,000-7,500 miles or 6-12 months, using synthetic oil is recommended.
Timing Belt Replacement:
Every 60,000-90,000 miles or 5-7 years, critical to prevent engine damage.
Spark Plug Replacement:
Every 30,000-60,000 miles, depending on spark plug type (standard vs. platinum/iridium).
Coolant Flush Interval:
Every 2-3 years or 30,000 miles.
Engine Oil Specification:
SAE 5W-40 synthetic oil meeting VW 502 00 / 505 00 standards is highly recommended for V6 engines. Check manual for specific approval codes.
Coolant Type:
G 12 or G 12+ coolant (pink/red) or compatible silicate-free antifreeze. Dilute 50/50 with distilled water.
Power Steering Fluid Type:
G 004 000 M2 or compatible CHF 11S fluid.
Common Problems Engine:
Timing belt failure (if not replaced on schedule), coolant leaks (especially around water pump and thermostat housing), oil leaks from valve cover gaskets and oil pan, distributor O-ring leaks.
Common Problems Electrical:
Clogged sunroof drains leading to water ingress, failing climate control modules, intermittent power window issues, frayed wiring in door hinges.
Common Problems Suspension:
Worn control arm bushings, failing strut mounts, tie rod end wear.
Common Problems Transmission:
Automatic transmission 'limp mode' issues (often related to solenoids or transmission control module), clutch wear on manual transmissions.
Oil Filter:
Mann-Filter W712/5, Mahle OC 52, Bosch 0 242 235 603 (Example parts - verify with VIN).
Air Filter:
Mann-Filter C35156/2, Mahle LX 75 (Example parts - verify with VIN).
Cabin Filter:
Not standard on all models, but if equipped, typically Mann-Filter CU 3030 or equivalent.
Heritage:
Audi has a long history dating back to the early 20th century, known for its engineering innovation, particularly in quattro all-wheel drive technology and diesel engine development.
Previous Generation:
The C4 generation replaced the Audi 100 C3, which was noted for its aerodynamic 'teardrop' design. The C4 adopted a more conventional, yet still sleek, design language.
Successor:
The Audi 100 was rebranded as the Audi A6 starting with the next generation (C5).
Production Years C4:
1990-1994
Manufacturing Locations:
Germany (primarily Ingolstadt)
