Does the Mazda Demio fail the MOT on noise, emissions and leaks more than it should?
The Mazda Demio records 5.55 noise, emissions and leaks failure items per 100 initial MOT tests (2019–2024), against 9.88 expected for a car of the same age mix: less than expected for its class and age (−4.33, 95% interval −5.07 to −3.59). It ranks 649 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 Mazda Demio by registration
What exactly fails on noise, emissions and leaks?
The most frequent DVSA defect wording in this group on the Mazda Demio is “Emissions levels exceed default limits”, recorded 115 times in 2019–2024.
| DVSA defect wording | Items | Per 100 tests |
|---|---|---|
| Emissions levels exceed default limits | 115 | 1.66 |
| Engine MIL illuminated indicating a malfunction | 78 | 1.13 |
| Lambda coefficient outside the default limits or the range specified by the manufacturer | 65 | 0.94 |
| Emissions levels exceed the manufacturer's specified limits | 48 | 0.69 |
| Emissions test unable to be completed | 44 | 0.64 |
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 6,922 (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
Other pages for this model
Mazda Demio 2002 · Mazda Demio 2003 · Mazda Demio in the Netherlands · Mazda Demio by postcode area · Mazda Demio body, chassis and structure failures · Mazda Demio brakes failures · Mazda Demio vehicle identification failures · Mazda Demio lamps, reflectors and electrics failures · Mazda Demio seat belts and airbags failures · Mazda Demio steering failures · Mazda Demio suspension failures · Mazda Demio tyres failures · Mazda Demio visibility failures