2005 Porsche Cayman — MOT failures & pass rate
Across 909 MOT tests, the 2005 Porsche Cayman recorded an 84.8% pass rate. Against coupes & convertibles of a similar age (22.3% fail rate), the 2005 Cayman comes out 7.1pp better. Failures cluster in lighting & signalling, suspension and emissions & environmental.
What the MOT record shows
No single area dominates — lighting & signalling (6.5%) and suspension (4.5%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are headlamp aim, catalyst emissions and rigid brake pipes — headlamp aim alone was recorded 40 times.
A 120-150k example is materially riskier than a 30-60k one: 15.0% versus 9.9%.
Brakes is the most common advisory, noted on 29.4% of tests — work that passed today but is likely due soon.
The trend is worsening — 11.8% of tests failed in 2021 against 15.8% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 6.5% | 59 |
| 2 | Suspension | 4.5% | 41 |
| 3 | Emissions & environmental | 4.4% | 40 |
| 4 | Brakes | 4.4% | 40 |
| 5 | Tyres | 2.1% | 19 |
| 6 | Visibility | 2.0% | 18 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Headlamp aim | 40 |
| 2 | Catalyst emissions | 36 |
| 3 | Rigid brake pipes | 29 |
| 4 | Coil spring | 26 |
| 5 | Position lamp | 22 |
| 6 | Wipers | 15 |
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 | 29.4% | 267 |
| 2 | Tyres | 19.5% | 177 |
| 3 | Suspension | 13.3% | 121 |
| 4 | Other defects | 11.7% | 106 |
| 5 | Lighting & signalling | 6.3% | 57 |
| 6 | Emissions & environmental | 5.0% | 45 |
Failure rate by mileage
Higher-mileage cars tend to fail more — often the most useful guide to real condition.
| Mileage band | Tests | Fail rate |
|---|---|---|
| 30-60k | 202 | 9.9% |
| 60-90k | 397 | 15.9% |
| 90-120k | 246 | 17.9% |
| 120-150k | 40 | 15.0% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 187 | 11.8% |
| 2022 | 185 | 14.1% |
| 2023 | 193 | 19.2% |
| 2024 | 173 | 15.0% |
| 2025 | 171 | 15.8% |
What to check before buying a 2005 Cayman
The failure pattern for this year is specific enough to inspect against: lighting & signalling accounted for 6.5% of tests. Start there.
- Lighting & signalling (6.5% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Suspension (4.5% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
- Emissions & environmental (4.4% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
Repair costs are rough UK ballpark ranges to set expectations, not quotes — actual prices vary widely by car, parts and garage.
Frequently asked questions
How many 2005 Porsche Caymans pass their MOT?
84.8% of the 909 2005 Porsche Cayman MOT tests in this dataset passed — a 15.2% fail rate.
What is the most common MOT failure on a 2005 Porsche Cayman?
Lighting & signalling, recorded in 6.5% of tests, followed by suspension (4.5%).
Does the 2005 Cayman get worse with mileage?
Its MOT fail rate rises from 9.9% in the 30-60k band to 15.0% in the 120-150k band.
Methodology & source. Based on 909 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.