Does the Ford Sierra fail the MOT on noise, emissions and leaks more than it should?
The Ford Sierra records 4.45 noise, emissions and leaks failure items per 100 initial MOT tests (2019–2024), against 7.32 expected for a car of the same age mix: less than expected for its class and age (−2.87, 95% interval −3.27 to −2.47). It ranks 598 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 Ford Sierra by registration
What exactly fails on noise, emissions and leaks?
The most frequent DVSA defect wording in this group on the Ford Sierra is “Emissions levels exceed default limits”, recorded 488 times in 2019–2024.
| DVSA defect wording | Items | Per 100 tests |
|---|---|---|
| Emissions levels exceed default limits | 488 | 2.76 |
| Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users | 69 | 0.39 |
| Emissions test unable to be completed | 68 | 0.38 |
| Lambda coefficient outside the default limits or the range specified by the manufacturer | 47 | 0.27 |
| Emissions levels exceed the manufacturer's specified limits | 42 | 0.24 |
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 17,679 (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 Ford Sierra gets a noise, emissions and leaks advisory, how often does it fail next time?
7.0% of Ford Sierra MOTs with a noise, emissions and leaks advisory were followed by a fail in the same group at the next MOT, typically 12.2 months and 696 miles later (1,113 advisories followed).
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 1,113 (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
Ford Sierra by postcode area · Ford Sierra body, chassis and structure failures · Ford Sierra brakes failures · Ford Sierra vehicle identification failures · Ford Sierra lamps, reflectors and electrics failures · Ford Sierra road wheels failures · Ford Sierra seat belts and airbags failures · Ford Sierra steering failures · Ford Sierra suspension failures · Ford Sierra tyres failures · Ford Sierra visibility failures