Audi A3 vs Audi A4 s line: reliability comparison
MOT pass rates, common faults and mileage compared from real UK MOT data.
Audi A3
78%
MOT pass rate · 586,036 vehicles
Audi A4 s line
78%
MOT pass rate · 90 vehicles
Verdict: On MOT pass rate the Audi A3 (78%) and Audi A4 s line (78%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Head to head
| Measure | Audi A3 | Audi A4 s line |
|---|---|---|
| MOT pass rate | 78% | 78% |
| MOT failure rate | 22% | 22% |
| Faults & advisories per test | 1.8 | 0.1 ✓ |
| Dangerous-fault share | 3% ✓ | 8% |
| Average mileage | 112,882 mi | 117,784 mi |
| Sample size (vehicles) | 586,036 | 90 |
Most common faults
Audi A3
- Offside Front Tyre worn close to legal limit/worn on edge (5.2.3 (e))
- Nearside Front Tyre worn close to legal limit/worn on edge (5.2.3 (e))
- Nearside Front Tyre worn close to the legal limit (4.1.E.1)
- Offside Front Tyre worn close to the legal limit (4.1.E.1)
- Nearside Rear Tyre worn close to the legal limit (4.1.E.1)
- Offside Rear Tyre worn close to the legal limit (4.1.E.1)
Audi A4 s line
- Nearside Front Tyre slightly damaged/cracking or perishing Wearing close to guides (5.2.3 (d) (ii))
- Nearside Rear Tyre worn close to legal limit/worn on edge (5.2.3 (e))
- Offside Rear Tyre worn close to legal limit/worn on edge (5.2.3 (e))
- Nearside Front Lower Suspension arm ball joint excessively worn (5.3.4 (a) (i))
- Offside Front Lower Suspension arm ball joint excessively worn (5.3.4 (a) (i))
- Rear Brake pad(s) less than 1.5 mm thick (1.1.13 (a) (ii))
Reliability FAQ
On MOT pass rate the Audi A3 (78%) and Audi A4 s line (78%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Full Audi A3 report Full Audi A4 s line report Most reliable cars
Pass rates are computed over completed (pass/fail) MOT tests. Reliability also depends on age, mileage and upkeep — see each model's page for the full picture.