2018 Porsche Cayenne — MOT failures & pass rate
Across 10,179 MOT tests, the 2018 Porsche Cayenne recorded a 91.7% pass rate. Large SUVs of a similar age fail 10.3% of the time, so this is 2.0pp better than the group it competes with. Failures cluster in tyres, visibility and lighting & signalling.
What the MOT record shows
One area stands out: tyres, recorded in 4.5% of tests against 1.5% for the next-worst category.
At component level the recurring items are wipers, headlamp aim and coil spring — wipers alone was recorded 131 times.
Mileage matters less than usual here: the 2018 Cayenne fails 7.0% of the time in the 0-30k band and 10.8% at 120-150k, a spread of only 3.8 points.
The petrol cars hold up better: 6.8% fail against 11.3% for diesel, a 4.5-point gap across 9,268 tests.
Tyres is the most common advisory, noted on 17.1% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 4.5% | 463 |
| 2 | Visibility | 1.5% | 150 |
| 3 | Lighting & signalling | 1.3% | 135 |
| 4 | Suspension | 1.1% | 115 |
| 5 | Brakes | 1.0% | 106 |
| 6 | Emissions & environmental | 0.8% | 84 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Wipers | 131 |
| 2 | Headlamp aim | 121 |
| 3 | Coil spring | 106 |
| 4 | Brake pads | 103 |
| 5 | Registration plates | 102 |
| 6 | Tread depth | 90 |
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 | 17.1% | 1,739 |
| 2 | Brakes | 9.8% | 996 |
| 3 | Other defects | 7.0% | 708 |
| 4 | Visibility | 2.3% | 234 |
| 5 | Suspension | 1.6% | 160 |
| 6 | Emissions & environmental | 0.8% | 77 |
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 | 3,115 | 7.0% |
| 30-60k | 5,050 | 8.1% |
| 60-90k | 1,730 | 11.1% |
| 90-120k | 231 | 11.3% |
| 120-150k | 37 | 10.8% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 6,108 | 6.8% |
| Diesel | 3,160 | 11.3% |
| Hybrid | 911 | 8.1% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 2,178 | 7.9% |
| 2022 | 2,022 | 7.0% |
| 2023 | 1,974 | 7.8% |
| 2024 | 2,036 | 10.1% |
| 2025 | 1,969 | 8.9% |
What to check before buying a 2018 Cayenne
The failure pattern for this year is specific enough to inspect against: tyres accounted for 4.5% of tests. Start there.
- Tyres (4.5% 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.
- Visibility (1.5% of tests): Wipers, washers, mirrors and screen damage — usually inexpensive, but check for chips in the driver's line of sight. Typical repair: £15–£150.
- Lighting & signalling (1.3% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
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 2018 Porsche Cayennes pass their MOT?
91.7% of the 10,179 2018 Porsche Cayenne MOT tests in this dataset passed — a 8.3% fail rate.
What is the most common MOT failure on a 2018 Porsche Cayenne?
Tyres, recorded in 4.5% of tests, followed by visibility (1.5%).
Does the 2018 Cayenne get worse with mileage?
Its MOT fail rate rises from 7.0% in the 0-30k band to 10.8% in the 120-150k band.
Methodology & source. Based on 10,179 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.