2018 Audi A8 — MOT failures & pass rate
5,229 MOT tests on the 2018 Audi A8 are in this dataset, and 93.8% of them passed. Against executive cars of a similar age (10.8% fail rate), the 2018 A8 comes out 4.7pp better. Failures cluster in tyres, visibility and lighting & signalling.
What the MOT record shows
No single area dominates — tyres (3.8%) and visibility (1.1%) are close, so failures are spread across several systems rather than one weak point.
At component level the recurring items are tread depth, registration plates and brake pads — tread depth alone was recorded 62 times.
Mileage matters less than usual here: the 2018 A8 fails 6.3% of the time in the 0-30k band and 6.6% at 150k+, a spread of only 0.2 points.
Fuel type barely separates them — petrol fails 5.8% of the time against 6.3% for diesel.
Advisories point at the next bill rather than this one: tyres was flagged on 15.6% of tests without failing them.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 3.8% | 199 |
| 2 | Visibility | 1.1% | 55 |
| 3 | Lighting & signalling | 0.8% | 44 |
| 4 | Brakes | 0.8% | 39 |
| 5 | Other defects | 0.6% | 31 |
| 6 | Emissions & environmental | 0.5% | 26 |
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 | 62 |
| 2 | Registration plates | 56 |
| 3 | Brake pads | 44 |
| 4 | Washers | 34 |
| 5 | Headlamp aim | 27 |
| 6 | Malfunction indicator lamp | 26 |
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 | 15.6% | 818 |
| 2 | Brakes | 9.1% | 477 |
| 3 | Other defects | 4.3% | 225 |
| 4 | Visibility | 3.0% | 155 |
| 5 | Suspension | 2.7% | 143 |
| 6 | Lighting & signalling | 0.5% | 25 |
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 | 1,563 | 6.3% |
| 30-60k | 2,257 | 6.3% |
| 60-90k | 961 | 6.0% |
| 90-120k | 290 | 4.5% |
| 120-150k | 97 | 5.1% |
| 150k+ | 61 | 6.6% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Diesel | 4,075 | 6.3% |
| Petrol | 1,154 | 5.8% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 1,074 | 7.1% |
| 2022 | 1,069 | 5.3% |
| 2023 | 1,059 | 6.4% |
| 2024 | 1,017 | 5.2% |
| 2025 | 1,010 | 6.7% |
What to check before buying a 2018 A8
On a 2018 A8, tyres is what the MOT record says goes wrong most — it appeared in 3.8% of tests. Check these areas before you commit.
- Tyres (3.8% 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 (1.1% 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 (0.8% 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 Audi A8s pass their MOT?
93.8% of the 5,229 2018 Audi A8 MOT tests in this dataset passed — a 6.2% fail rate.
What is the most common MOT failure on a 2018 Audi A8?
Tyres, recorded in 3.8% of tests, followed by visibility (1.1%).
Does the 2018 A8 get worse with mileage?
Its MOT fail rate rises from 6.3% in the 0-30k band to 6.6% in the 150k+ band.
Methodology & source. Based on 5,229 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.