Target Audience:
Professional technicians, independent repair shops, and A4/S4 owners performing their own repairs and parts ordering.
Segment:
Entry-level to near-luxury sport sedan and wagon (Avant), with high-performance S4 variant.
Key Advantage:
quattro all-wheel drive availability across the range when many rivals were front-wheel drive only.
Build Quality:
High-grade interior materials and rigid body structure for the era.
Engines:
1.8T, 3.0 V6, and 4.2 V8 (S4).
Drivetrain:
Front-wheel drive or quattro permanent all-wheel drive.
Body Styles:
Sedan, Avant (wagon), and Cabriolet.
Engine Assembly:
Cylinder block, heads, pistons, camshafts, valvetrain, gaskets and seals.
Fuel & Air Delivery:
Fuel pumps, injectors, throttle body, air cleaner, intake manifolds.
Cooling System:
Radiator, water pump, thermostat, hoses, expansion tank, fans.
Exhaust System:
Manifolds, catalytic converters, mufflers, tailpipes, hangers.
Turbocharging (1.8T):
Turbocharger, wastegate, intercooler, boost hoses.
Transmission & Clutch:
Manual and automatic transmission internals, clutch kit, flywheel, CV joints, driveshaft.
Suspension & Steering:
Control arms, ball joints, bushings, shocks, springs, power steering components.
Brakes:
Discs, pads, calipers, master cylinder, ABS components, lines.
Wheels:
Factory wheel options, hubs, bearings, lug hardware.
Body & Exterior:
Panels, bumpers, fenders, doors, hood, trunk lid, mirrors, glass, weatherstrips.
Interior & Trim:
Seats, dashboard, door panels, headliner, carpeting.
Electrical:
Wiring, relays, switches, sensors, alternator, starter, ignition components.
Lighting:
Headlights, taillights, fog lights, turn signals, interior lamps.
HVAC:
Heater core, blower motor, A/C compressor, condenser, evaporator, controls.
Accessories:
Wipers, washers, seat heaters, sunroof, antenna components.
Part Numbers:
Genuine Audi part numbers for accurate ordering.
Illustrations:
Exploded-view diagrams showing part relationships and orientation.
Quantity Data:
Required quantities per vehicle for each part.
Cross-References:
Superseded and alternative part number references.
Applicability Notes:
Part usage notes indicating model year and engine applicability.
Group Structure:
Organized by factory main groups and sub-groups for fast lookup.
File Format:
PDF (searchable, bookmarked, zoomable)
Compatibility:
Windows, macOS, Linux, iOS, and Android — any device with a PDF reader
Requirements:
A PDF reader application (e.g. Adobe Acrobat Reader, free)
Searchability:
Fully text searchable for fast lookup of any topic
Print Quality:
High-resolution digital pages, printable at full clarity
Binding Type:
N/A — digital download, no physical binding
Paper Type:
N/A — digital download, no physical paper
Base Engine:
1.8L turbocharged inline-4 (1.8T, code AMB).
Mid Engine:
3.0L V6 (code AVK).
S4 Engine:
4.2L V8 (code BBK), 2004-2005 S4.
1.8T Output:
Approximately 170 hp (CVT/FWD) to 190 hp (quattro).
3.0 V6 Output:
Approximately 220 hp.
4.2 V8 Output:
Approximately 340 hp (S4).
Fuel Delivery:
Sequential multi-port electronic fuel injection.
Fuel Type:
Premium unleaded recommended.
Turbocharger:
K03 turbocharger with intercooler (1.8T models).
NHTSA Crash Tests:
Strong frontal and side ratings for the era; N/A - consult NHTSA for exact scores per model year.
IIHS Evaluation:
N/A - not specified in this document.
ABS:
4-wheel anti-lock braking system.
Traction Control:
ASR traction control.
Stability Control:
ESP electronic stabilization program.
Airbags:
Dual front, side thorax, and side curtain airbags.
Seatbelts:
Pretensioners and force limiters.
Structure:
Reinforced passenger safety cell with crumple zones.
Oil Change:
Approximately every 10,000 miles or 12 months (long-life schedule); severe use more frequent.
Timing Belt (1.8T/3.0):
Approximately 75,000-105,000 miles; confirm per year/engine.
Brake Fluid:
Replace approximately every 2 years.
Engine Oil:
Synthetic 5W-30 or 5W-40 meeting VW 502.00 standard.
Coolant:
G12/G12+ (pink/purple) phosphate-free coolant.
Transmission Fluid:
Automatic/Tiptronic: Audi-spec ATF; Manual: SAE 75W-90 gear oil; Multitronic: CVT-specific fluid.
Known Issues / Common Wear Items
Control Arms:
Front control arm bushings are a common wear item on B6 chassis.
1.8T Sludge:
Oil sludge risk if oil changes are neglected; strict oil maintenance required.
Coil Packs:
Ignition coil failures common on 1.8T engines.
Manufacturer:
Audi AG, Ingolstadt, Germany; part of the Volkswagen Group.
Heritage:
Audi introduced quattro permanent all-wheel drive in 1980, defining its performance identity.
B6 Generation:
A4 introduced for 2002 model year (US) on the B6 platform with new styling and revised suspensions.
S4 Evolution:
S4 moved from the 2.7 bi-turbo V6 (B5) to the 4.2L V8 with the B6 generation (2004).
Primary Production:
Ingolstadt, Germany.
Secondary Production:
Neckarsulm, Germany for some variants.
