2021 Audi A8 — MOT failures & pass rate
The 2021 Audi A8 passed 95.7% of its 649 recorded MOT tests. Against executive cars of a similar age (9.5% fail rate), the 2021 A8 comes out 5.2pp better. Failures cluster in tyres, visibility and brakes.
What the MOT record shows
No single area dominates — tyres (3.1%) and visibility (0.8%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are tread depth, washers and malfunction indicator lamp — tread depth alone was recorded 6 times.
A 60-90k example is materially riskier than a 0-30k one: 10.0% versus 4.4%.
Advisories point at the next bill rather than this one: tyres was flagged on 11.9% of tests without failing them.
The trend is worsening — 0.0% of tests failed in 2023 against 3.1% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 3.1% | 20 |
| 2 | Visibility | 0.8% | 5 |
| 3 | Brakes | 0.6% | 4 |
| 4 | Emissions & environmental | 0.6% | 4 |
| 5 | Lighting & signalling | 0.6% | 4 |
| 6 | Other defects | 0.3% | 2 |
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 | 6 |
| 2 | Washers | 4 |
| 3 | Malfunction indicator lamp | 4 |
| 4 | Registration plates | 3 |
| 5 | Brake pads | 2 |
| 6 | Headlamp cleaning device | 2 |
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 | 11.9% | 77 |
| 2 | Brakes | 6.5% | 42 |
| 3 | Other defects | 2.3% | 15 |
| 4 | Visibility | 2.0% | 13 |
| 5 | Emissions & environmental | 0.3% | 2 |
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 | 275 | 4.4% |
| 30-60k | 279 | 2.5% |
| 60-90k | 70 | 10.0% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 428 | 5.4% |
| Petrol | 111 | 1.8% |
| Hybrid | 110 | 2.7% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2023 | 39 | 0.0% |
| 2024 | 302 | 6.3% |
| 2025 | 293 | 3.1% |
What to check before buying a 2021 A8
On a 2021 A8, tyres is what the MOT record says goes wrong most — it appeared in 3.1% of tests. Check these areas before you commit.
- Tyres (3.1% 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 (0.8% 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.
- Brakes (0.6% 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 2021 Audi A8s pass their MOT?
95.7% of the 649 2021 Audi A8 MOT tests in this dataset passed — a 4.3% fail rate.
What is the most common MOT failure on a 2021 Audi A8?
Tyres, recorded in 3.1% of tests, followed by visibility (0.8%).
Does the 2021 A8 get worse with mileage?
Its MOT fail rate rises from 4.4% in the 0-30k band to 10.0% in the 60-90k band.
Methodology & source. Based on 649 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.