2004 Audi S4 Reliability ReportKeepScore 62/100 · top failure points · buy or avoid
Quick Facts · 2004 Audi S4
- Outscores the 2002 Audi S4 by 17 points — one of the stronger nearby years to consider.
- The system most likely to surface first: engine timing chain system (critical severity).
- Has 1 NHTSA recall on record — the most notable involves the exterior lighting:headlights.
2004 Audi S4: Buy or Avoid?
The 2004 Audi S4 delivers exhilarating V8 performance and Quattro grip, making it an incredibly engaging driver's car. However, its complex engineering, particularly the rear-mounted timing chain system, introduces a significant risk of catastrophic and extremely expensive engine failure. This vehicle is a high-reward, high-risk proposition that demands a substantial budget for both purchase and ongoing maintenance.
The 2004 Audi S4 is a magnificent performance machine that is a joy to drive, but it's unequivocally a high-risk purchase due to the well-documented, catastrophic timing chain issue. Only consider this car if you have a significant budget for proactive or reactive repairs, or can confirm the timing chain service has…
Best Model Years
2006-2008 (B7 generation) S4 models, though they retain the same engine with similar timing chain risks, often have slightly better updated electronics and a more modern interior.
Years to Avoid
Avoid the earliest B6 S4 models (2004-2005) if the timing chain service history is unknown or unverified, as they are now at prime mileage for issues.
Biggest Strengths
- Potent 4.2L V8 engine performance (when functional)
- Excellent Quattro all-wheel-drive system
- High-quality, well-appointed interior
2004 Audi S4 — Known Trouble Spots
The systems that tend to fail first on the 2004 Audi S4, with the typical mileage window when each becomes a concern. Detailed repair-cost ranges and exact what-to-check inspection notes are in the full report.
Plastic timing chain guides and hydraulic tensioners are prone to wear, leading to noise and eventual failure. Repair requires engine removal, making it a 25-40 hour job, often exceeding the vehicle's value.
Common leaks from valve cover gaskets, cam tensioner seals, oil cooler seals, and the PCV system components. Neglecting these can lead to low oil pressure and damage.
The complex multi-link front suspension system has numerous bushings and control arms that wear out, causing clunks, looseness, and premature tire wear. Requires frequent replacement.
2004 Audi S4 Mileage Danger Zones
The mileage windows when the 2004 Audi S4 most commonly needs attention. Plan ahead, budget accordingly, and inspect before you cross each threshold.
Early Warning Zone
At this mileage, issues are generally minor, typically limited to ignition coil packs or minor electrical gremlins that are inexpensive to fix. Focus on proactive fluid changes and inspections.
Maintenance & Wear Zone
Front suspension components, such as control arms and bushings, will likely begin to show wear. Brake system overhaul is common. Watch for the first signs of oil leaks.
Elevated Risk Zone
This is where the infamous timing chain system starts to become a significant concern. Listen for chain rattle on startup. More extensive oil leaks and potential automatic transmission issues may also surface.
High Risk & Major Overhaul Zone
At this mileage, if the timing chain service hasn't been done, it's a critical ticking time bomb. Expect major suspension overhauls and potentially significant engine or transmission work.
2004 Audi S4 Ownership Cost Outlook
What it typically costs to keep the 2004 Audi S4 on the road. Full 5-year cost-of-ownership projection and major-failure-risk forecast are in the report.
Annual Maintenance
$800-1,500 (excluding major repairs)
Moderate Repairs
$500-2,500 frequently for items like suspension, larger oil leaks, or minor electrical issues.
How Long Does the 2004 Audi S4 Last?
Assume any 2004 S4 with over 80,000 miles that lacks detailed records of a timing chain service will need this multi-thousand-dollar repair in the near future; factor this into your purchase price as a non-negotiable expense.
What 2004 Audi S4 Owners Actually Say
What Owners Love
- Exhilarating V8 exhaust note and performance
- Superb grip and handling from the Quattro AWD system
- High-quality, comfortable, and well-designed interior
- Timeless, understated exterior styling
Common Frustrations
- Astronomical potential repair costs for the timing chain
- Poor fuel economy (typical of a V8 performance car)
- Frequent and costly maintenance demands
- Oil leaks are a constant battle for higher mileage cars
Who Should Buy the 2004 Audi S4?
Best For
- Automotive enthusiasts with a strong mechanical aptitude and DIY skills.
- Individuals with a substantial discretionary income for maintenance and repairs.
- Drivers seeking thrilling V8 performance and AWD grip as a weekend car.
Not Ideal For
- Budget-conscious buyers or those seeking low ownership costs.
- Anyone needing reliable daily transportation without a significant repair fund.
How the 2004 Audi S4 Compares to Rivals
The 2004 S4 offers a unique blend of V8 power and AWD in a compact sedan, but its specific major engine flaw makes its ownership proposition far riskier than many direct and indirect competitors.
More Reliable Than
- 2004 Mercedes-Benz C32 AMG (less overall complexity, though still expensive)
- Some older, highly modified Japanese imports (often more neglected)
Comparable To
- 2004 BMW E46 M3 (different set of expensive issues - subframe, VANOS, rod bearings)
- 2004 Porsche 911 (996 generation) (IMS bearing and RMS concerns, but different ownership experience)
Safety Recalls on the 2004 Audi S4
1 recall on record from NHTSA. Check your VIN atnhtsa.gov to see if the repair was performed.
EXTERIOR LIGHTING:HEADLIGHTS
ON CERTAIN PASSENGER VEHICLES, THERE IS A POSSIBILITY OF XENON HEADLAMP COATING DEGRADATION OVER TIME. THE LUMINOUS TRANSMITTANCE OF THE HEADLAMP MAY DECREASE OVER A PERIOD OF TIME.
What breaks on the 2004 Audi S4?
Full reliability breakdown — engine, transmission, rust, electrical. With repair costs and mileage danger zones.
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Audi S4 — Year-by-Year Comparison
Compare KeepScores across nearby years of the Audi S4. Click any year for its full report.
Competing 2004s Worth a Look
Similar class, similar year range — ranked by KeepScore.
Relevant Products for Your 2004 Audi S4
Parts and accessories matched to your 2004 Audi S4
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Frequently Asked Questions
Just bought a 2004 Audi S4? Keep it that way.
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