The Carrera S is the higher-output 997 with a 3.8-litre flat-six, wider rear track, larger brakes, and 19-inch wheels as standard. The 997.1 (2005-2008, M97.01, 355 hp) shares the IMS bearing and bore scoring risks of its era, with the 3.8 being slightly more susceptible to bore scoring than the 3.6 Carrera. The 997.2 (2009-2012, 9A1 DFI, 385 hp) eliminates IMS entirely and greatly reduces bore scoring risk. Widely regarded as one of the best-sounding naturally aspirated sports cars of its generation.
Exceptional flat-six soundtrack
Huge specialist network and parts supply
3.8 more prone to bore scoring than 3.6
Higher consumable costs than base Carrera
Buy if: You want the definitive naturally aspirated 911 experience with more power and wider stance, and can verify bore scope and IMS bearing status on 997.1 models.
Avoid if: You cannot budget for potential engine work on a 997.1 or are uncomfortable with the bore scoring risk on the 3.8 engine.
Expected Annual Maintenance Costs
Common Problems
Alusil cylinder liners score from thermal distortion; the 3.8 is more affected than the 3.6 · more· less
Bore scoring occurs when the Lokasil/Alusil cylinder lining is damaged, allowing pistons to contact bare aluminium. The 3.8-litre Carrera S engine is more susceptible than the 3.6 Carrera, with specialist estimates suggesting 5-10% of 997.1 3.8 engines are affected over their lifetime. Cylinder 6 runs hottest and is most vulnerable. Symptoms include a rhythmic metallic ticking at cold idle that fades as the engine warms, and increasing oil consumption. Short trips and infrequent use accelerate the problem because condensation dilutes the oil film. A bore scope inspection before purchase (€100-200 at any Porsche specialist) is essential. If scoring is found, repair requires machining and fitting billet aluminium sleeves with forged pistons: €5,000-6,000 for cylinder work alone, or €10,000-12,000 for a full engine rebuild including removal. The 997.2 DFI engine (9A1) has a different block design and bore scoring is extremely rare on these cars.
Intermediate shaft bearing can fail on pre-2009 cars, causing catastrophic engine damage · more· less
The 997.1 Carrera S (2005-2008) uses an improved IMS bearing compared to the 996, and failure rates are estimated at around 1-3% over the car's lifetime. Early 2005 cars with the single-row bearing have a slightly higher risk; from mid-2006 the improved non-serviceable larger bearing reduced failures further. When the bearing fails, metal debris circulates through the engine, destroying bearings and scoring surfaces. Preventive IMS bearing upgrade using LN Engineering kits costs €2,000-3,000 including gearbox removal. If the bearing fails catastrophically, expect €8,000-12,000 for an engine rebuild. Cars with over 120,000 km that have not experienced failure are considered lower risk. The 997.2 (2009-2012) uses the 9A1 DFI engine which has no IMS bearing at all.
Front coolant pipes corrode internally and rubber hoses perish, causing coolant leaks · more· less
The 997's front-mounted radiators connect to the rear engine via long coolant pipes running under the car. The aluminium crossover pipes corrode internally over time, and rubber connecting hoses perish with age and heat cycles. A sweet coolant smell near the front of the car is the typical first sign. This is one of the most common issues on 997s across all model years and generations. Parts cost €200-400, but labour adds significantly due to accessibility as the front axle carrier may need to be lowered. Total repair at a specialist runs €800-1,500. If a coolant leak goes unnoticed, overheating can cause catastrophic engine damage, making regular coolant system inspection critical.
Crankshaft rear seal leaks oil onto clutch and transmission bellhousing · more· less
The rear main seal (RMS) is a known weak point on M97 and 9A1 engines. When it fails, oil seeps onto the flywheel and clutch, potentially contaminating the clutch disc and requiring clutch replacement alongside. The seal itself costs under €50, but the gearbox must be removed for access, requiring 8-10 hours of labour. Most specialists recommend combining RMS replacement with clutch, IMS bearing upgrade (on 997.1), and AOS replacement since the gearbox is already out. Standalone RMS repair costs €1,200-1,800. Combined with clutch replacement, expect €2,000-3,500 total. An estimated 15-20% of 997s develop this leak over their lifetime.
Internal diaphragm fails, causing oil ingestion into the intake and lean running · more· less
The AOS recirculates crankcase gases back into the intake manifold. When its internal diaphragm degrades, liquid oil passes into the intake, causing lean running conditions that can accelerate bore scoring. Symptoms are often subtle: slightly irregular idle, occasional misfire codes, and marginal fuel trim drift. The part costs €100-150, but labour is 3-4 hours due to difficult access behind the intake manifold. Total replacement at a specialist runs €400-800. Only genuine Porsche AOS units are recommended, as aftermarket replacements have higher failure rates. Preventive replacement at 80,000-100,000 km is widely recommended by specialists.
Coil springs crack and break due to corrosion, especially on cars in wet climates · more· less
A well-known 997 issue where coil springs crack at their lower end where water collects and corrodes the metal. Owners sometimes hear a loud crack while the car is parked. Broken spring fragments can damage tyres. Front springs are more commonly affected than rears. Springs must be replaced in pairs per axle. Parts cost approximately €150-250 per pair, with about 2 hours of fitting. Total replacement including alignment runs €400-800 per axle. Cars with PASM adaptive suspension are slightly more susceptible due to different spring rates and increased stress. Carrera S models run stiffer springs than base Carreras.
Front-mounted condensers are vulnerable to stone impacts, causing refrigerant leaks · more· less
The 997 has twin A/C condensers mounted low on either side of the front bumper, directly behind the air intake grilles. Road debris and stone impacts puncture the thin aluminium fins and tubes, causing refrigerant leaks. Some units fail in as little as 4-5 years. OEM condensers cost approximately €250-350 each from Porsche. Aftermarket alternatives are available from around €80-100 each. Total repair including degassing, replacement, and regassing runs €500-1,200 depending on whether one or both condensers need replacement and the choice of parts. Stone guards or mesh protectors fitted behind the grilles can prevent recurrence.
Factory cable crimp develops resistance, causing slow cranking and charging issues · more· less
Early 997.1 models (primarily 2005-2006) have a known issue with a poor factory crimp on the battery/starter/alternator cable. The connection develops resistance over time, reducing both alternator charging output and starter motor cranking speed. Symptoms worsen with engine heat, sometimes causing complete failure to start when the engine is hot. Porsche issued a Technical Service Bulletin for this issue. The updated cable costs approximately €80-100. A dealer installation runs around €500-600 total, while an independent specialist charges €300-400.
997.1 needs careful inspection; 997.2 is considerably lower risk
The 997 Carrera S spans two distinct risk profiles. The 997.1 (2005-2008) carries IMS bearing and bore scoring risks, with the 3.8-litre engine being slightly more susceptible to bore scoring than the 3.6 Carrera. A bore scope inspection and IMS bearing status check are essential before purchasing any 997.1. The 997.2 (2009-2012) eliminates both headline engine concerns with its direct-injection 9A1 engine. Both generations share coolant system vulnerabilities, rear main seal concerns, and suspension spring issues. With proper pre-purchase inspection and proactive cooling system maintenance, the 997 Carrera S can be a reliable and rewarding ownership experience.
Recalls and Technical Service Bulletins
Fuel system vapour line leak (2005-2008 997.1 models)
Verify completed
Alternator cable TSB / technical campaign (2005-2006 models)
Verify completed
Takata airbag inflator (various 2004-2012 models)
Critical - verify completed
Headlight wiring harness (early 997.1 models)
Verify completed
Contact Porsche with the VIN at recall.porsche.com to verify all recalls and technical campaigns have been completed. The Takata airbag recall is particularly important and applies across many production years.
Warranty Status
Factory warranty (2 years)
Expired on all 997 models
Porsche Approved warranty
Not available for 997-era cars (typically limited to cars under 15 years)
Third-party warranty
Available but typically excludes IMS, bore scoring, and known engine failures
All 997 models are outside their original 2-year factory warranty. Porsche Approved extended warranty is generally not available for cars of this age. Third-party warranties exist but nearly always exclude pre-existing conditions and known M97/9A1 engine failure modes. Budget for repairs directly rather than relying on warranty coverage.
This report is for informational purposes only and does not constitute professional advice. Estimates may be inaccurate. Always have a qualified specialist inspect the vehicle before purchase. We accept no liability for decisions made based on this information.