Porsche Cayman MOT pass rate & common failures
73,734 MOT tests on the Porsche Cayman (2004–2023) give it a 91.3% pass rate. Against coupes & convertibles of a similar age (15.3% fail rate), the Cayman comes out 6.7pp better. Its most common failure areas are lighting & signalling, tyres and brakes.
Best and worst Cayman years
Ranked across Cayman years with at least 1,000 tests. Older cars fail more simply because they are older — compare years close together in age before drawing conclusions.
What the MOT record shows
Build year matters more than the headline suggests: 2020 cars pass 96.1% of the time while 2006 cars manage 84.0%, a 12.2-point spread.
No single area dominates — lighting & signalling (3.4%) and tyres (2.6%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are headlamp aim, rigid brake pipes and position lamp — headlamp aim alone was recorded 1,307 times.
A 150k+ example is materially riskier than a 0-30k one: 18.9% versus 3.6%.
Advisories point at the next bill rather than this one: tyres was flagged on 15.4% of tests without failing them.
How it compares
By model year
Every Cayman model year with a usable sample. Years with their own detailed report are linked.
| Year | Tests | Pass rate | Fail rate | Most common failure |
|---|---|---|---|---|
| 2005 | 909 | 84.8% | 15.2% | Lighting & signalling |
| 2006 | 8,368 | 84.0% | 16.0% | Lighting & signalling |
| 2007 | 7,945 | 85.5% | 14.4% | Lighting & signalling |
| 2008 | 5,004 | 85.8% | 14.2% | Lighting & signalling |
| 2009 | 3,561 | 90.5% | 9.5% | Lighting & signalling |
| 2010 | 2,920 | 90.6% | 9.4% | Brakes |
| 2011 | 2,799 | 91.6% | 8.4% | Brakes |
| 2012 | 1,684 | 93.1% | 6.9% | Brakes |
| 2013 | 4,823 | 93.2% | 6.8% | Tyres |
| 2014 | 6,339 | 93.9% | 6.1% | Tyres |
| 2015 | 5,729 | 95.3% | 4.7% | Tyres |
| 2016 | 5,183 | 95.5% | 4.5% | Tyres |
| 2017 | 4,725 | 95.1% | 4.9% | Tyres |
| 2018 | 6,530 | 94.9% | 5.1% | Tyres |
| 2019 | 4,338 | 95.3% | 4.8% | Tyres |
| 2020 | 1,426 | 96.1% | 3.9% | Tyres |
| 2021 | 933 | 96.9% | 3.1% | Tyres |
| 2022 | 507 | 95.9% | 4.1% | Tyres |
Most common failures (all years)
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Lighting & signalling | 3.4% | 2,532 |
| 2 | Tyres | 2.6% | 1,919 |
| 3 | Brakes | 2.1% | 1,534 |
| 4 | Suspension | 1.8% | 1,316 |
| 5 | Emissions & environmental | 1.4% | 1,065 |
| 6 | Visibility | 1.3% | 938 |
| 7 | Other defects | 0.5% | 361 |
| 8 | Body, structure & corrosion | 0.4% | 325 |
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 | 1,307 |
| 2 | Rigid brake pipes | 1,279 |
| 3 | Position lamp | 1,264 |
| 4 | Tread depth | 1,198 |
| 5 | Catalyst emissions | 905 |
| 6 | Wipers | 621 |
| 7 | Coil spring | 610 |
| 8 | Registration plates | 578 |
Top advisory categories
Advisories aren't failures, but they flag work likely needed soon — useful when budgeting.
| # | Category | % of tests with advisory | Tests |
|---|---|---|---|
| 1 | Tyres | 15.4% | 11,373 |
| 2 | Brakes | 14.6% | 10,776 |
| 3 | Suspension | 5.3% | 3,944 |
| 4 | Other defects | 5.1% | 3,751 |
| 5 | Visibility | 2.4% | 1,775 |
| 6 | Emissions & environmental | 2.3% | 1,697 |
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 | 24,967 | 3.6% |
| 30-60k | 25,179 | 7.8% |
| 60-90k | 15,591 | 13.4% |
| 90-120k | 6,318 | 18.1% |
| 120-150k | 1,360 | 18.2% |
| 150k+ | 307 | 18.9% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 13,794 | 8.5% |
| 2022 | 14,658 | 8.2% |
| 2023 | 14,907 | 8.8% |
| 2024 | 14,991 | 9.0% |
| 2025 | 15,384 | 8.8% |
What to check before buying a Porsche Cayman
- Lighting & signalling (3.4% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Tyres (2.6% 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.
- Brakes (2.1% 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.
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?
91.3% of the 73,734 Porsche Cayman MOT tests in this dataset passed, an 8.7% fail rate, across model years 2004–2023.
What does the Porsche Cayman most often fail its MOT on?
Lighting & signalling, recorded in 3.4% of tests, then tyres (2.6%).
Which Cayman years are best and worst for MOT results?
2020 has the best pass rate at 96.1% and 2006 the weakest at 84.0%, from 1,426 and 8,368 tests respectively.
How much does mileage affect Cayman MOT results?
Fail rates run at 3.6% for cars in the 0-30k band and 18.9% for 150k+, a 15.3-point difference.
Methodology & source. Based on 73,734 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.