2008 Porsche Cayman — MOT failures & pass rate
5,004 MOT tests on the 2008 Porsche Cayman are in this dataset, and 85.8% of them passed. Against coupes & convertibles of a similar age (21.1% fail rate), the 2008 Cayman comes out 6.9pp better. Failures cluster in lighting & signalling, brakes and suspension.
What the MOT record shows
Lighting & signalling dominates the failure mix at 8.1% of all tests — 4.2 points clear of brakes, so it is the first thing to check.
At component level the recurring items are position lamp, rigid brake pipes and headlamp aim — position lamp alone was recorded 284 times.
Mileage is the strongest signal on the record: 5.0% of 0-30k cars fail, rising to 23.9% once past 150k — 4.8× the risk.
Advisories point at the next bill rather than this one: brakes was flagged on 25.3% of tests without failing them.
The trend is worsening — 12.3% of tests failed in 2021 against 15.6% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 8.1% | 406 |
| 2 | Brakes | 3.9% | 194 |
| 3 | Suspension | 3.2% | 160 |
| 4 | Emissions & environmental | 2.7% | 134 |
| 5 | Tyres | 2.6% | 129 |
| 6 | Visibility | 2.1% | 104 |
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 | 284 |
| 2 | Rigid brake pipes | 174 |
| 3 | Headlamp aim | 155 |
| 4 | Catalyst emissions | 107 |
| 5 | Stop lamp | 96 |
| 6 | Wipers | 89 |
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 | 25.3% | 1,264 |
| 2 | Tyres | 18.5% | 927 |
| 3 | Other defects | 10.1% | 505 |
| 4 | Suspension | 9.7% | 487 |
| 5 | Emissions & environmental | 5.2% | 262 |
| 6 | Lighting & signalling | 3.7% | 185 |
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 | 281 | 5.0% |
| 30-60k | 1,566 | 11.0% |
| 60-90k | 1,982 | 15.2% |
| 90-120k | 931 | 17.6% |
| 120-150k | 196 | 25.0% |
| 150k+ | 46 | 23.9% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 1,028 | 12.3% |
| 2022 | 1,002 | 13.2% |
| 2023 | 1,028 | 16.5% |
| 2024 | 978 | 13.5% |
| 2025 | 968 | 15.6% |
What to check before buying a 2008 Cayman
On a 2008 Cayman, lighting & signalling is what the MOT record says goes wrong most — it appeared in 8.1% of tests. Check these areas before you commit.
- Lighting & signalling (8.1% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (3.9% 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.
- Suspension (3.2% 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.
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 2008 Porsche Caymans pass their MOT?
85.8% of the 5,004 2008 Porsche Cayman MOT tests in this dataset passed — a 14.2% fail rate.
What is the most common MOT failure on a 2008 Porsche Cayman?
Lighting & signalling, recorded in 8.1% of tests, followed by brakes (3.9%).
Does the 2008 Cayman get worse with mileage?
Its MOT fail rate rises from 5.0% in the 0-30k band to 23.9% in the 150k+ band.
Methodology & source. Based on 5,004 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.