Does the Audi S4 fail the MOT on noise, emissions and leaks more than it should?
The Audi S4 records 3.97 noise, emissions and leaks failure items per 100 initial MOT tests (2019–2024), against 5.23 expected for a car of the same age mix: less than expected for its class and age (−1.26, 95% interval −1.68 to −0.84). It ranks 472 of 678 models on noise, emissions and leaks (1 = most failures above expected).
Data release dvsa-2024-v2 (24 Sep 2026) · page updated 30 Sep 2026 · all models on noise, emissions and leaks · check a Audi S4 by registration
What exactly fails on noise, emissions and leaks?
The most frequent DVSA defect wording in this group on the Audi S4 is “Emissions levels exceed default limits”, recorded 116 times in 2019–2024.
| DVSA defect wording | Items | Per 100 tests |
|---|---|---|
| Emissions levels exceed default limits | 116 | 1.03 |
| Engine MIL illuminated indicating a malfunction | 89 | 0.79 |
| Lambda coefficient outside the default limits or the range specified by the manufacturer | 85 | 0.76 |
| Emissions levels exceed the manufacturer's specified limits | 53 | 0.47 |
| Emissions test unable to be completed | 36 | 0.32 |
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 11,213 (initial tests) · Method: failure items (major and minor) grouped by DVSA's defect tree; wordings with 30+ items · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV
If a Audi S4 gets a noise, emissions and leaks advisory, how often does it fail next time?
7.3% of Audi S4 MOTs with a noise, emissions and leaks advisory were followed by a fail in the same group at the next MOT, typically 12.1 months and 4,324 miles later (710 advisories followed).
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 710 (advisories followed) · Method: the same vehicles followed to their next ordinary MOT · Updated: 30 Sep 2026 · Release: dvsa-2024-v2 · CSV
Other pages for this model
Audi S4 2019 · Audi S4 2020 · Audi S4 in the Netherlands · Audi S4 by postcode area · Audi S4 body, chassis and structure failures · Audi S4 brakes failures · Audi S4 vehicle identification failures · Audi S4 lamps, reflectors and electrics failures · Audi S4 road wheels failures · Audi S4 seat belts and airbags failures · Audi S4 steering failures · Audi S4 suspension failures · Audi S4 tyres failures · Audi S4 visibility failures