Porsche Cayman S MOT pass rate & common failures
1,384 MOT tests on the Porsche Cayman S (2005–2021) give it a 91.0% pass rate. Against all cars of a similar age (22.9% fail rate), the Cayman S comes out 13.8pp better. Its most common failure areas are lighting & signalling, brakes and tyres.
What the MOT record shows
No single area dominates — lighting & signalling (3.5%) and brakes (2.9%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are position lamp, tread depth and headlamp aim — position lamp alone was recorded 32 times.
A 90-120k example is materially riskier than a 0-30k one: 15.8% versus 6.0%.
Advisories point at the next bill rather than this one: brakes was flagged on 16.7% of tests without failing them.
How it compares
By model year
Every Cayman S model year with a usable sample. Years with their own detailed report are linked.
| Year | Tests | Pass rate | Fail rate | Most common failure |
|---|---|---|---|---|
| 2006 | 226 | 84.1% | 15.9% | Lighting & signalling |
| 2007 | 156 | 82.0% | 17.9% | Lighting & signalling |
| 2008 | 59 | 93.2% | 6.8% | Lighting & signalling |
| 2009 | 63 | 88.9% | 11.1% | Suspension |
| 2011 | 54 | 92.6% | 7.4% | Visibility |
| 2012 | 47 | 93.6% | 6.4% | Lighting & signalling |
| 2013 | 728 | 94.9% | 5.1% | Tyres |
Most common failures (all years)
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 3.5% | 48 |
| 2 | Brakes | 2.9% | 40 |
| 3 | Tyres | 2.4% | 33 |
| 4 | Suspension | 2.1% | 29 |
| 5 | Visibility | 1.5% | 21 |
| 6 | Emissions & environmental | 1.1% | 15 |
| 7 | Steering | 0.6% | 8 |
| 8 | Body, structure & corrosion | 0.6% | 8 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Position lamp | 32 |
| 2 | Tread depth | 24 |
| 3 | Headlamp aim | 23 |
| 4 | Rigid brake pipes | 21 |
| 5 | Coil spring | 19 |
| 6 | Catalyst emissions | 17 |
| 7 | Brake discs | 13 |
| 8 | Wipers | 12 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Brakes | 16.7% | 231 |
| 2 | Tyres | 14.2% | 196 |
| 3 | Other defects | 6.1% | 84 |
| 4 | Suspension | 5.3% | 74 |
| 5 | Emissions & environmental | 3.1% | 43 |
| 6 | Visibility | 2.5% | 35 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 0-30k | 251 | 6.0% |
| 30-60k | 546 | 6.2% |
| 60-90k | 423 | 12.1% |
| 90-120k | 114 | 15.8% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 280 | 8.9% |
| 2022 | 284 | 9.5% |
| 2023 | 268 | 6.7% |
| 2024 | 278 | 10.8% |
| 2025 | 274 | 9.1% |
What to check before buying a Porsche Cayman S
- Lighting & signalling (3.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (2.9% of tests): Pads/discs are routine wear; binding, imbalance or corroded pipes are more serious — test for pulling under braking. Typical repair: £100–£350 per axle.
- Tyres (2.4% of tests): Usually a quick, known-cost fix, but check tread, age and uneven wear (which can hint at alignment or suspension issues). Typical repair: £50–£120 per tyre.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
What is the MOT pass rate for the Porsche Cayman S?
91.0% of the 1,384 Porsche Cayman S MOT tests in this dataset passed, a 9.0% fail rate, across model years 2005–2021.
What does the Porsche Cayman S most often fail its MOT on?
Lighting & signalling, recorded in 3.5% of tests, then brakes (2.9%).
How much does mileage affect Cayman S MOT results?
Fail rates run at 6.0% for cars in the 0-30k band and 15.8% for 90-120k, a 9.8-point difference.
Methodology & source. Based on 1,384 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-27. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.