Audi 100, A6 & S4 Service & Repair Manuals
The Audi 100 and early A6 (Type 4A) are famous for their solid build and bodies that hold up remarkably well against rust. Whether you’re keeping a high-mileage 2.5 TDI on the road or looking after a performance S4 or S6 with the legendary 5-cylinder turbo or V8 engine, these cars are a top choice for home mechanics who like straightforward, classic German engineering.
We offer these manuals in three flexible formats to suit your workspace:
Technical Coverage for the Audi 100 / A6 / S4 Range
This manual provides broad coverage for the 4A (C4) chassis, including the wide range of petrol and diesel engines found in the UK.
Petrol Engines (Standard & Performance)
- 4-Cylinder & 5-Cylinder: Detailed guides for the 1.6 (ABB), 1.8 20V (ADR), 2.0 (AAE, ABK, ADW), 2.0 16V (ACE), and the smooth 2.3 (AAR).
- S4 / S6 2.2 Turbo: Specialist data for the legendary 2.2 20V turbo (AAN).
- V6 & V8 Power: Technical specs for the 2.4 (AFM), 2.6 (ACZ), 2.8 (AFC), and the flagship S4/S6 V8 (ABH, AEC, AHK).
Diesel Engines
- 1.9 & 2.5 TDI: Essential maintenance for the 1.9 TDI (1Z, AHU) and the famous 5-cylinder 2.5 TDI (AEL, AAT, ABP).
- 2.4 D: Coverage for the naturally aspirated 2.4 Diesel (AAS).
Why Use a Haynes Manual for Your Audi 4A?
- 5-Cylinder Turbo Care: The AAN engine is a masterpiece but needs the right care. Our manual covers boost leak checks and the specific oil cooling needs that keep these engines going for years.
- Quattro Drivetrain Maintenance: If your Audi has the Quattro system, we provide the technical data for differential oil changes and checking the prop-shaft bearings.
- Interactive Fault Finder (Online Edition): Older Audis can develop odd electrical issues. Our digital tool helps you find common faults, from central locking vacuum leaks to instrument cluster glitches.
- UK-Specific Data: All specs - from the correct oil grades for the UK climate to the brake disc sizes - are tailored for UK-market cars.
- Wiring Diagrams: High-resolution diagrams make it easier to trace faults in the electric windows, sunroof, or the early climate control systems.
FAQ: Audi 100 & A6 (C4) Maintenance Tips
Q: How often should I change the cambelt on the 2.5 TDI?
A: For the 5-cylinder TDI, it is best to change the cambelt every 60,000 miles or 5 years. This is a vital job because the belt also drives the water pump; our manual shows you how to check both.
Q: Why is my S4/S6 engine bay smelling of oil?
A: A common issue on the 2.2 Turbo (AAN) is the oil feed lines or rocker cover gaskets perishing over time. Our manual helps you find these leaks early to keep the engine clean and safe.
Q: My steering wheel feels strange. What is Procon-Ten?
A: This was Audi's own safety system before airbags were everywhere. It uses cables to pull the steering wheel away from you in a crash. Our manual provides the checks to make sure the cables are correctly in place.
Classic Build, Modern Help
The Audi 4A generation is built to last. Keep your classic Audi running smoothly and avoid high garage bills with a Haynes Service & Repair Manual. From a basic oil change to getting the car through its MOT, we give you the confidence to do the work yourself.
