Does the Toyota iQ fail the MOT on noise, emissions and leaks more than it should?
The Toyota iQ records 1.56 noise, emissions and leaks failure items per 100 initial MOT tests (2019–2024), against 4.38 expected for a car of the same age mix: less than expected for its class and age (−2.82, 95% interval −2.95 to −2.70). It ranks 595 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 Toyota iQ by registration
What exactly fails on noise, emissions and leaks?
The most frequent DVSA defect wording in this group on the Toyota iQ is “Engine MIL illuminated indicating a malfunction”, recorded 514 times in 2019–2024.
| DVSA defect wording | Items | Per 100 tests |
|---|---|---|
| Engine MIL illuminated indicating a malfunction | 514 | 0.50 |
| Lambda coefficient outside the default limits or the range specified by the manufacturer | 434 | 0.42 |
| Emissions test unable to be completed | 195 | 0.19 |
| Emissions levels exceed default limits | 178 | 0.17 |
| Emissions levels exceed the manufacturer's specified limits | 111 | 0.11 |
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 103,601 (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 Toyota iQ gets a noise, emissions and leaks advisory, how often does it fail next time?
4.7% of Toyota iQ 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 5,270 miles later (780 advisories followed).
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 780 (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
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