Audi A4 vs Audi S1 competition quattro: reliability comparison
MOT pass rates, common faults and mileage compared from real UK MOT data.
Audi A4
76%
MOT pass rate · 568,515 vehicles
Audi S1 competition quattro
100%
MOT pass rate · 8 vehicles
Verdict: On MOT pass rate the Audi A4 (76%) and Audi S1 competition quattro (100%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Head to head
| Measure | Audi A4 | Audi S1 competition quattro |
|---|---|---|
| MOT pass rate | 76% | 100% ✓ |
| MOT failure rate | 24% | 0% ✓ |
| Faults & advisories per test | 1.9 | 0.0 ✓ |
| Dangerous-fault share | 2% | — ✓ |
| Average mileage | 133,841 mi | 50,585 mi |
| Sample size (vehicles) | 568,515 | 8 |
Most common faults
Audi A4
- 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)
- Under-trays fitted obscuring some underside components
- Nearside Front Tyre worn close to legal limit/worn on edge (5.2.3 (e))
Audi S1 competition quattro
No fault breakdown available.
Reliability FAQ
On MOT pass rate the Audi A4 (76%) and Audi S1 competition quattro (100%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.
Full Audi A4 report Full Audi S1 competition quattro 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.