Audi S4 CAKA
"If you're buying a performance Audi, expect shit to break. Show love to your car and it will love you back."
Known Issues
Timing Chain Tensioner FailureCRITICAL
Hydraulic tensioners on the secondary timing chain are prone to failure. When tensioners fail, chain rattle begins, plastic guides crack and break, and cam phaser values go out of spec. Left unaddressed this leads to catastrophic engine damage.
Crank Pulley / Accessory Belt FailureHIGH
The harmonic balancer / crank pulley is known to fail, potentially causing the accessory belt to melt the supercharger belt tensioner and damage the coolant return pipe. Failures have been reported at speed on the freeway with cascading damage to surrounding components.
Valve Cover Gasket Oil LeaksMODERATE
Valve cover gaskets are reported to leak oil at higher mileages. Commonly discovered during other under-bonnet inspections. Can worsen and lead to oil contacting hot engine components if not addressed.
Official Recalls
Inflator module may rupture on deployment, sending metal fragments toward occupants
Same Takata inflator rupture risk on 2009 model year vehicles
Buying Checklist
Service Reality
Strong Points
Also Found In
Time Bomb Parts Inspect Proactively
Tuning Risk If This Example Has Been Modified
MODERATEA software-only ECU tune on this platform can generally be reverted to a stock-reading file. A reduced supercharger pulley and/or larger crank pulley, unlike a software tune, is a physical part swap that is directly checkable by inspecting the fitted pulley against factory specification, so this specific and very common upgrade is meaningfully harder to fully disguise than tuning on a turbocharged engine, though a seller could still swap the stock pulleys back in before a sale.
As with the related B8.5 platform, this engine's positive-displacement supercharger delivers boost in an inherently linear, predictable way, and a base Stage 1 software tune is broadly treated by the community as low-risk. Once a pulley is added for Stage 2+, established tuners are explicit that supporting hardware (intake, heat exchanger, and often an HPFP upgrade) is required, not optional, particularly for ethanol-blended tunes. A real owner account of repeated supercharger clutch failures under one tuner's map, resolved by switching to a different, better-calibrated tune, is a useful illustration that tuner quality meaningfully affects mechanical outcomes on this platform, not just the claimed power figure. A car showing dual-pulley power claims without evidence of HPFP or cooling system upgrades represents more risk than a documented, properly built example.
This profile reflects consensus from Audizine (including a long-running, multi-year tuning development thread specific to this platform and real HPFP failure reports with fault codes), a detailed specialist technical guide (STR Performance) covering the EA837 engine family, and multiple tuner-published technical requirements (034Motorsport, Integrated Engineering, Jackal Motorsports), not manufacturer-confirmed limits. Reported power figures vary by pulley ratio, fuel/ethanol blend, and individual tuner calibration quality, which owner accounts specifically indicate can meaningfully affect component longevity (e.g. supercharger clutch wear) independent of the power figure claimed. Treat any suspected tuned or previously tuned example as needing a full pre-purchase inspection (supercharger pulley and belt check, snout bearing play check, fuel rail pressure/HPFP condition, coolant system condition) rather than relying on an OBD scan alone.
Buying Advice
The CAKA-engined B8 S4 is a genuinely exciting performance car, but it demands respect and a committed maintenance budget. The single biggest risk is timing chain tensioner failure, which can be a catastrophic and expensive repair if ignored, so always perform a cold-start listen before any purchase. Budget for proactive replacement of tensioners, guides, and the crank pulley on any high-mileage example, and factor in elevated running costs compared to mainstream vehicles. This is a rewarding car for an owner who maintains it properly, but a financial trap for anyone expecting neglect tolerance.
Community Sentiment
Owners who maintain the car diligently are broadly positive about performance and driving enjoyment, but timing chain tensioner failures and generally high running costs generate significant frustration in the community. The consensus is clear: this engine rewards responsible ownership and punishes neglect.
Frequently Asked Questions
❯How reliable is the Audi S4 CAKA?
The Audi S4 CAKA has a reliability score of 54/100, rated "RISKY". Thrilling supercharged V6, but timing chain tensioners are the real risk
❯What are the common problems with the CAKA?
The most frequently reported issues are Timing Chain Tensioner Failure, Crank Pulley / Accessory Belt Failure, Valve Cover Gasket Oil Leaks. See the Known Issues section above for symptoms, affected mileage, and repair costs.
❯Does the CAKA have timing chain tensioner failure problems?
Yes, this is a documented issue on the CAKA, typically appearing around 80,000-160,000 km. Hydraulic tensioners on the secondary timing chain are prone to failure. When tensioners fail, chain rattle begins, plastic guides crack and break, and cam phaser values go out of spec. Left unaddressed this leads to catastrophic engine damage. Typical repair cost: €1,500-3,500. DIY difficulty: Hard.
❯Does the CAKA have crank pulley / accessory belt failure problems?
Yes, this is a documented issue on the CAKA, typically appearing around 100,000-180,000 km. The harmonic balancer / crank pulley is known to fail, potentially causing the accessory belt to melt the supercharger belt tensioner and damage the coolant return pipe. Failures have been reported at speed on the freeway with cascading damage to surrounding components. Typical repair cost: €400-1,200. DIY difficulty: Moderate.
❯Does the CAKA have valve cover gasket oil leaks problems?
Yes, this is a documented issue on the CAKA, typically appearing around 80,000-150,000 km. Valve cover gaskets are reported to leak oil at higher mileages. Commonly discovered during other under-bonnet inspections. Can worsen and lead to oil contacting hot engine components if not addressed. Typical repair cost: €300-800. DIY difficulty: Moderate.
❯Is the CAKA worth buying used?
The CAKA-engined B8 S4 is a genuinely exciting performance car, but it demands respect and a committed maintenance budget. The single biggest risk is timing chain tensioner failure, which can be a catastrophic and expensive repair if ignored, so always perform a cold-start listen before any purchase. Budget for proactive replacement of tensioners, guides, and the crank pulley on any high-mileage example, and factor in elevated running costs compared to mainstream vehicles. This is a rewarding car for an owner who maintains it properly, but a financial trap for anyone expecting neglect tolerance.
❯What should I check before buying a used CAKA?
Before buying, check: Perform a cold-start and listen carefully for any timing chain rattle in the first 10 seconds of running; Request full service history and verify oil changes were done every 10,000 km or less with correct VW 502/504 spec oil; Check VIN against NHTSA recall database and confirm the Takata airbag recall has been completed at a dealer; Inspect valve covers and surrounding areas for oil seepage or burning oil smell around the engine bay; Visually inspect crank pulley rubber damper for cracking, delamination, or wobble at idle.
❯How many km will a CAKA last?
There's no fixed mileage limit, it depends on maintenance. The parts worth budgeting for proactively are: Timing chain tensioners and guides (80,000-100,000 km), Crank pulley / harmonic balancer (100,000 km), Supercharger drive belt and tensioner (60,000-80,000 km), Valve cover gaskets (100,000-150,000 km). Engines that clear these checkpoints with documented maintenance commonly continue well beyond typical ownership periods.
❯Is there a recall for the air bags – frontal passenger side inflator module on the CAKA?
Inflator module may rupture on deployment, sending metal fragments toward occupants Remedy: Dealer replacement of passenger-side airbag inflator module under recall
❯Is there a recall for the air bags – frontal passenger side inflator module (2009 model year) on the CAKA?
Same Takata inflator rupture risk on 2009 model year vehicles Remedy: Dealer replacement of passenger-side airbag inflator module under recall
❯How much does it cost to maintain a CAKA?
Estimated ownership cost is €4,500–10,500 over 3 years, covering consumables, preventive timing chain and crank pulley work, and incidental repairs on higher-mileage examples, based on known issues and typical service needs.
❯What is the real-world fuel consumption of the CAKA?
Owners report real-world fuel consumption of around 11 L/100km.
❯What oil should I use in a CAKA, and how often?
Community-reported real-world usage suggests changing oil every 10,000 km using VW 502.00 / 504.00 compliant 5W-30 or 5W-40 full synthetic, often more conservative than the official service schedule.
❯Is it safe to tune or remap the CAKA?
The CAKA is commonly modified, with a moderate risk level when pushed beyond stock. Typical weak points under tuning: High-pressure fuel pump (HPFP), Supercharger snout bearing and clutch, Cooling system (heat exchanger, coolant pump).
❯What other cars use the CAKA engine?
The CAKA is also found in: Audi S5 B8 (2009–2012), Audi Q7 3.0 TFSI Supercharged (limited S-line applications, CAKA), Audi A6 3.0 TFSI (related EA837 supercharged family, lower-output CCAA variant).
❯Why does the CAKA have a bad reputation?
Thrilling supercharged V6, but timing chain tensioners are the real risk The biggest recurring complaint is Timing Chain Tensioner Failure. Owners who maintain the car diligently are broadly positive about performance and driving enjoyment, but timing chain tensioner failures and generally high running costs generate significant frustration in the community. The consensus is clear: this engine rewards responsible ownership and punishes neglect.