2017 Audi A8 — MOT failures & pass rate
The 2017 Audi A8 passed 93.6% of its 3,597 recorded MOT tests. That is 5.1 percentage points better than executive cars of a similar age, which fail at 11.6%. Failures cluster in tyres, emissions & environmental and brakes.
What the MOT record shows
No single area dominates — tyres (4.3%) and emissions & environmental (1.3%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are tread depth, malfunction indicator lamp and registration plates — tread depth alone was recorded 76 times.
Mileage matters less than usual here: the 2017 A8 fails 4.8% of the time in the 0-30k band and 4.3% at 150k+, a spread of only 0.4 points.
Tyres is the most common advisory, noted on 15.9% of tests — work that passed today but is likely due soon.
The trend is improving — the fail rate fell from 7.3% in 2021 to 5.8% in 2025, as the worst-kept examples leave the fleet.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 4.3% | 154 |
| 2 | Emissions & environmental | 1.3% | 47 |
| 3 | Brakes | 0.9% | 34 |
| 4 | Visibility | 0.7% | 25 |
| 5 | Lighting & signalling | 0.6% | 21 |
| 6 | Other defects | 0.5% | 17 |
Most common specific failures
The exact components most often recorded as failures — more specific than the categories above.
| # | Failure item | Times recorded |
|---|---|---|
| 1 | Tread depth | 76 |
| 2 | Malfunction indicator lamp | 43 |
| 3 | Registration plates | 27 |
| 4 | Brake pads | 22 |
| 5 | Headlamp aim | 11 |
| 6 | Washers | 11 |
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 | 15.9% | 573 |
| 2 | Brakes | 8.5% | 306 |
| 3 | Other defects | 4.2% | 151 |
| 4 | Visibility | 2.6% | 94 |
| 5 | Suspension | 2.6% | 92 |
| 6 | Emissions & environmental | 0.7% | 26 |
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 | 589 | 4.8% |
| 30-60k | 1,557 | 6.7% |
| 60-90k | 904 | 7.1% |
| 90-120k | 332 | 8.4% |
| 120-150k | 97 | 1.0% |
| 150k+ | 116 | 4.3% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 3,231 | 6.2% |
| Petrol | 366 | 8.5% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 738 | 7.3% |
| 2022 | 742 | 6.2% |
| 2023 | 713 | 6.6% |
| 2024 | 714 | 6.2% |
| 2025 | 690 | 5.8% |
What to check before buying a 2017 A8
The failure pattern for this year is specific enough to inspect against: tyres accounted for 4.3% of tests. Start there.
- Tyres (4.3% 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 (1.3% of tests): More common on older diesels (DPF/EGR) — can be expensive; check for warning lights and smoke. Typical repair: £100–£600.
- Brakes (0.9% 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.
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 Audi A8s pass their MOT?
93.6% of the 3,597 2017 Audi A8 MOT tests in this dataset passed — a 6.4% fail rate.
What is the most common MOT failure on a 2017 Audi A8?
Tyres, recorded in 4.3% of tests, followed by emissions & environmental (1.3%).
Does the 2017 A8 get worse with mileage?
Its MOT fail rate rises from 4.8% in the 0-30k band to 4.3% in the 150k+ band.
Methodology & source. Based on 3,597 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.