2018 Audi TT — MOT failures & pass rate
22,502 MOT tests on the 2018 Audi TT are in this dataset, and 92.7% of them passed. That is 1.8 percentage points better than coupes & convertibles of a similar age, which fail at 9.1%. Failures cluster in tyres, lighting & signalling and brakes.
What the MOT record shows
One area stands out: tyres, recorded in 4.9% of tests against 1.6% for the next-worst category.
At component level the recurring items are tread depth, headlamp aim and brake pads — tread depth alone was recorded 744 times.
Mileage is the strongest signal on the record: 5.4% of 0-30k cars fail, rising to 14.5% once past 90-120k — 2.7× the risk.
Fuel type barely separates them — petrol fails 7.2% of the time against 8.7% for diesel.
Tyres is the most common advisory, noted on 21.8% of tests — work that passed today but is likely due soon.
The trend is worsening — 7.0% of tests failed in 2021 against 8.8% in 2025, the usual pattern as a fleet ages.
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 4.9% | 1,101 |
| 2 | Lighting & signalling | 1.6% | 356 |
| 3 | Brakes | 1.0% | 232 |
| 4 | Visibility | 0.9% | 213 |
| 5 | Seat belts & restraints | 0.5% | 109 |
| 6 | Other defects | 0.4% | 90 |
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 | 744 |
| 2 | Headlamp aim | 215 |
| 3 | Brake pads | 184 |
| 4 | Registration plates | 145 |
| 5 | Wipers | 121 |
| 6 | Washers | 108 |
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 | 21.8% | 4,907 |
| 2 | Brakes | 12.0% | 2,701 |
| 3 | Other defects | 4.7% | 1,055 |
| 4 | Visibility | 2.8% | 622 |
| 5 | Suspension | 1.0% | 234 |
| 6 | Lighting & signalling | 0.4% | 83 |
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 | 11,190 | 5.4% |
| 30-60k | 9,554 | 8.3% |
| 60-90k | 1,564 | 13.2% |
| 90-120k | 152 | 14.5% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 20,921 | 7.2% |
| Diesel | 1,581 | 8.7% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2021 | 4,735 | 7.0% |
| 2022 | 4,456 | 5.6% |
| 2023 | 4,475 | 7.0% |
| 2024 | 4,383 | 8.2% |
| 2025 | 4,453 | 8.8% |
What to check before buying a 2018 TT
The failure pattern for this year is specific enough to inspect against: tyres accounted for 4.9% of tests. Start there.
- Tyres (4.9% 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.
- Lighting & signalling (1.6% of tests): Often a cheap bulb, but persistent issues can mean wiring or corrosion in the units. Typical repair: £10–£150.
- Brakes (1.0% 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 2018 Audi TTs pass their MOT?
92.7% of the 22,502 2018 Audi TT MOT tests in this dataset passed — a 7.3% fail rate.
What is the most common MOT failure on a 2018 Audi TT?
Tyres, recorded in 4.9% of tests, followed by lighting & signalling (1.6%).
Does the 2018 TT get worse with mileage?
Its MOT fail rate rises from 5.4% in the 0-30k band to 14.5% in the 90-120k band.
Methodology & source. Based on 22,502 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.