2021 Audi A3 S Line 30 — MOT failures & pass rate
Across 3,150 MOT tests analysed for the 2021 Audi A3 S Line 30, the most common recorded failure areas were tyres, visibility and suspension. Its pass rate of 91.8% was in line with the average for cars of a similar age (91.2%).
How it compares
Top failure categories
| # | Category | % of tests affected | Tests |
|---|---|---|---|
| 1 | Tyres | 5.6% | 175 |
| 2 | Visibility | 1.1% | 35 |
| 3 | Suspension | 1.1% | 33 |
| 4 | Lighting & signalling | 0.9% | 29 |
| 5 | Brakes | 0.8% | 26 |
| 6 | Emissions & environmental | 0.7% | 21 |
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 | 70 |
| 2 | Shock absorbers | 32 |
| 3 | Headlamp aim | 30 |
| 4 | Washers | 24 |
| 5 | Brake pads | 22 |
| 6 | Wipers | 22 |
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 | 25.7% | 810 |
| 2 | Suspension | 7.8% | 244 |
| 3 | Other defects | 7.6% | 239 |
| 4 | Brakes | 7.0% | 222 |
| 5 | Visibility | 2.0% | 64 |
| 6 | Road wheels | 0.4% | 11 |
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 | 1,635 | 6.8% |
| 30-60k | 1,301 | 9.5% |
| 60-90k | 177 | 10.2% |
Failure rate by age
By fuel type
| Fuel | Tests | Fail rate |
|---|---|---|
| Petrol | 2,636 | 7.7% |
| Diesel | 514 | 10.9% |
Trend over time
| Dataset year | Tests | Fail rate |
|---|---|---|
| 2023 | 74 | 5.4% |
| 2024 | 1,565 | 8.4% |
| 2025 | 1,511 | 8.2% |
What to check before buying a 2021 A3 S Line 30
Before buying a 2021 Audi A3 S Line 30, focus on the areas it most often fails on. Tyres accounted for 5.6% of tests for this year.
- Tyres (5.6% 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.
- Suspension (1.1% of tests): Worn drop links, bushes, springs or shocks — listen for knocks over bumps and check for uneven tyre wear. Typical repair: £150–£450 per corner.
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 A3 S Line 30s pass their MOT?
91.8% of the 3,150 2021 Audi A3 S Line 30 MOT tests in this dataset passed — a 8.2% fail rate.
What is the most common MOT failure on a 2021 Audi A3 S Line 30?
Tyres, recorded in 5.6% of tests, followed by visibility (1.1%).
Does the 2021 A3 S Line 30 get worse with mileage?
Its MOT fail rate rises from 6.8% in the 0-30k band to 10.2% in the 60-90k band.
Methodology & source. Based on 3,150 MOT tests. Dataset: DVSA MOT testing data (2021,2022,2023,2024,2025). Data last updated 2026-07-01. Figures reflect MOT-testable defects only — read the methodology for how these are calculated and what they don't measure.