2017 Bentley Mulsanne — MOT failures & pass rate
Across 430 MOT tests, the 2017 Bentley Mulsanne recorded a 94.7% pass rate. Against all cars of a similar age (12.6% fail rate), the 2017 Mulsanne comes out 7.3pp better. Failures cluster in tyres, emissions & environmental and other defects.
What the MOT record shows
No single area dominates — tyres (3.5%) and emissions & environmental (1.2%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are registration plates, malfunction indicator lamp and tyre pressure monitoring system — registration plates alone was recorded 8 times.
Tyres is the most common advisory, noted on 10.5% of tests — work that passed today but is likely due soon.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 3.5% | 15 |
| 2 | Emissions & environmental | 1.2% | 5 |
| 3 | Other defects | 0.9% | 4 |
| 4 | Brakes | 0.5% | 2 |
| 5 | Steering | 0.5% | 2 |
| 6 | Lighting & signalling | 0.2% | 1 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Registration plates | 8 |
| 2 | Malfunction indicator lamp | 3 |
| 3 | Tyre pressure monitoring system | 2 |
| 4 | Other components | 2 |
| 5 | Catalyst emissions | 1 |
| 6 | Wipers | 1 |
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 | 10.5% | 45 |
| 2 | Other defects | 2.8% | 12 |
| 3 | Brakes | 1.6% | 7 |
| 4 | Steering | 1.2% | 5 |
| 5 | Suspension | 0.5% | 2 |
| 6 | Emissions & environmental | 0.2% | 1 |
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 | 329 | 6.4% |
| 30-60k | 99 | 2.0% |
Failure rate by age
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 88 | 6.8% |
| 2022 | 94 | 7.4% |
| 2023 | 81 | 3.7% |
| 2024 | 84 | 2.4% |
| 2025 | 83 | 6.0% |
What to check before buying a 2017 Mulsanne
The failure pattern for this year is specific enough to inspect against: tyres accounted for 3.5% of tests. Start there.
- Tyres (3.5% 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.
- Emissions & environmental (1.2% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
- Other defects (0.9% of tests): Miscellaneous items not in the main categories. Typical repair: varies.
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 2017 Bentley Mulsannes pass their MOT?
94.7% of the 430 2017 Bentley Mulsanne MOT tests in this dataset passed — a 5.3% fail rate.
What is the most common MOT failure on a 2017 Bentley Mulsanne?
Tyres, recorded in 3.5% of tests, followed by emissions & environmental (1.2%).
Does the 2017 Mulsanne get worse with mileage?
Its MOT fail rate rises from 6.4% in the 0-30k band to 2.0% in the 30-60k band.
Methodology & source. Based on 430 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.