The 2004 Audi S4 Cabriolet is a high-performance luxury convertible powered by a 4.2-liter V8 engine producing 340 horsepower, mated to either a 6-speed manual or 6-speed Tiptronic automatic transmission. It combines all-wheel-drive capability with open-air touring, making it a compelling yet complex modern classic for enthusiasts.
Introduction and Subject Identity
The automotive landscape of the mid-2000s produced a unique class of over-engineered, high-displacement luxury cruisers. Among them, the 2004 Audi S4 Cabriolet (internally designated within the B6 generation) occupies a distinct niche. It merges the compact, executive styling of Audi’s mainstream A4 platform with an uncompromised, naturally aspirated V8 power plant and the legendary Quattro permanent all-wheel-drive system.
For potential buyers, restorers, and automotive enthusiasts in 2026, evaluating this vehicle requires looking past its initial luxury appeal. Two decades after its debut, the S4 Cabriolet is appreciated less as a daily commuter and more as an enthusiast project that demands careful maintenance, financial preparedness, and an understanding of its unique mechanical architecture. Resolving the inherent complexities of its drivetrain and folding soft-top mechanism is essential for anyone considering ownership.
Evolution and Technical Specifications
To understand the 2004 Audi S4 Cabriolet, one must examine how it differed from its sedan and avant (wagon) siblings. While the S4 sedan and avant debuted for the 2004 model year in North America, the Cabriolet body style rolled out slightly later in Europe and arrived on shores shortly thereafter, utilizing the B6 chassis architecture.
At the heart of the vehicle lies an all-aluminum 4.2-liter 40-valve V8 engine (engine code BHF/BBK depending on exact market specification). Unlike its turbocharged predecessors or modern turbocharged successors, this power plant relies on sheer displacement and high-revving capability to generate its output.
Key Performance and Mechanical Metrics
| Specification Feature | 2004 Audi S4 Cabriolet Detail |
|---|---|
| Engine Type | 4.2L Naturally Aspirated 90° V8 (40 valves) |
| Horsepower | 340 hp @ 7,000 RPM |
| Torque | 302 lb-ft (410 Nm) @ 3,500 RPM |
| Transmission Options | 6-speed manual or 6-speed Tiptronic automatic with DSP |
| Drivetrain | Quattro permanent all-wheel drive (Torsen T-3 center diff) |
| Curb Weight | Approximately 4,090 lbs (1,855 kg) |
| 0–60 mph Time | ~5.6 seconds (Manual) / ~5.9 seconds (Tiptronic) |
The integration of a heavy V8 engine directly over and ahead of the front axle profoundly shapes the car's driving dynamics. Combined with the structural reinforcements required to maintain chassis rigidity in a convertible, the Cabriolet is significantly heavier than its sedan counterpart. This weight penalty shifts the car's personality away from a razor-sharp track weapon toward a formidable, high-speed grand tourer.
Powertrain Dynamics and Real-World Performance
Driving the 2004 Audi S4 Cabriolet is defined heavily by its acoustic profile and power delivery. The 4.2-liter V8 produces a deep, baritone exhaust note that intensifies exponentially as the tachometer sweeps toward its 7,200 RPM redline.
The Manual vs. Tiptronic Debate
- 6-Speed Manual: Highly sought after by purists. The gated shift feel is mechanical, though throws can feel somewhat long. It allows the driver to exploit the torque curve fully and avoids the power parasitic losses associated with older torque-converter automatics.
- 6-Speed Tiptronic: Features steering-wheel-mounted paddle shifters and dynamic shift programs. While shifts are slower by modern standards, it offers relaxed cruising capability, making it popular among buyers seeking a straightforward cruiser.
Quattro All-Wheel Drive in a Convertible
The inclusion of Audi’s Quattro system provides a level of weather-agnostic stability rare in rear-wheel-drive sports convertibles of this era. Whether navigating rain-slicked mountain passes or dry pavement, power is actively distributed to maintain traction. However, this mechanical complexity adds weight and increases rotational mass, which impacts fuel economy, routinely registering in the mid-teens for city driving and low twenties on the highway.
Interior Ergonomics, Luxury, and Comfort
Inside the cabin, the 2004 Audi S4 Cabriolet reflects the peak of early-2000s Ingolstadt build quality. Soft-touch dashboard materials, dense plastics, and brushed aluminum or optional carbon-fiber trim pieces characterize the interior environment.
Seating and Ergonomics
The vehicle comes standard with deeply bolstered Recaro sport seats upholstered in Silk Nappa leather. These seats offer exceptional lateral support during spirited driving while remaining comfortable on long journeys. Heating functions, power adjustments, and memory settings were standard or widely opted features.
The Acoustic Soft-Top Experience
The fully automatic, three-layer acoustic fabric top is a masterpiece of engineering for its time. Operating via an electro-hydraulic mechanism controlled by a center-console switch, the top can be raised or lowered in approximately 21 seconds at speeds up to 18 mph. When closed, multiple insulation layers significantly dampen wind and road noise, allowing the cabin to rival the quietness of a fixed-roof coupe.
Ownership Considerations, Common Issues, and Maintenance
Operating a high-performance European car from the early 2000s requires a proactive approach to maintenance. The 4.2L V8 in the B6 S4 is famous for one specific mechanical layout choice: the timing chain is located at the back of the engine, facing the firewall.
1. Timing Chain Guides and Tensioners
Because the timing chain assembly sits against the transmission bellhousing, servicing the chain guides, tensioners, and slides requires engine removal (often referred to as a "service position" or complete engine-out procedure).
- Symptom: Rattle upon cold startup lasting more than 2 to 3 seconds.
- Mitigation: Listen carefully to cold starts during any pre-purchase inspection. Failure to address worn guides can lead to catastrophic engine interference.
2. Carbon Buildup
As a direct-injection engine (FSI variants arrived later, but early port-injection variants still require attention), intake valves are prone to carbon deposits over tens of thousands of miles, leading to sluggish throttle response and misfires if neglected. Regular intake cleaning is recommended.
3. Cooling System Vulnerabilities
Plastic coolant pipes, expansion tanks, and thermostats become brittle with age and thermal cycling. Cooling system overhauls are a standard preventative maintenance item to prevent warped cylinder heads or overheating events.
Frequently Asked Questions
Is the 2004 Audi S4 Cabriolet a reliable daily driver?
While mechanically robust when maintained, it is not recommended as a stress-free daily commuter due to its age, fuel consumption, and specialized maintenance requirements. It excels as a weekend car or second vehicle for enthusiasts who can stay ahead of preventative maintenance.
How much does a timing chain service cost on this model?
Because servicing the timing chains requires removing the entire engine and transmission assembly from the car, labor costs are substantial. Depending on the shop and the extent of components replaced (chains, guides, tensioners, clutch), costs frequently range from $3,000 to $6,000.
Does the convertible top leak or fail often?
The hydraulic system and fabric top are generally durable, but hydraulic cylinders can develop fluid leaks over time, and fabric tops can wear at folding crease points if left unconditioned. Regular cleaning and waterproofing of the canvas extend its lifespan significantly.
Are replacement parts difficult to source?
Routine maintenance parts (filters, brake components, suspension arms) are widely available through independent European parts suppliers. However, body panels specific to the Cabriolet and interior trim pieces are increasingly difficult to source new and often require looking to specialized salvage yards.
Conclusion and Buying Recommendation
The 2004 Audi S4 Cabriolet remains a captivating proposition: a soulful V8 engine, robust all-wheel-drive capability, and classic convertible styling wrapped in a premium German package. However, ownership rewards patience and financial preparation. Prospective buyers should prioritize examples with comprehensive, documented service histories—specifically verifying whether major preventative work like timing chain maintenance or cooling system overhauls has been completed. For the dedicated enthusiast, a well-kept S4 Cabriolet offers a rewarding driving experience that is increasingly rare in the modern automotive market.
