Does the BMW 4 Series fail the MOT on noise, emissions and leaks more than it should?
The BMW 4 Series records 0.37 noise, emissions and leaks failure items per 100 initial MOT tests (2019–2024), against 1.19 expected for a car of the same age mix: less than expected for its class and age (−0.82, 95% interval −0.85 to −0.79). It ranks 414 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 BMW 4 Series by registration
What exactly fails on noise, emissions and leaks?
The most frequent DVSA defect wording in this group on the BMW 4 Series is “Engine MIL illuminated indicating a malfunction”, recorded 913 times in 2019–2024.
| DVSA defect wording | Items | Per 100 tests |
|---|---|---|
| Engine MIL illuminated indicating a malfunction | 913 | 0.17 |
| Smoke opacity levels exceed the manufacturer's specified limit | 217 | 0.04 |
| Lambda coefficient outside the default limits or the range specified by the manufacturer | 192 | 0.04 |
| Emissions levels exceed default limits | 148 | 0.03 |
| Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users | 118 | 0.02 |
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 525,142 (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 BMW 4 Series gets a noise, emissions and leaks advisory, how often does it fail next time?
0.9% of BMW 4 Series MOTs with a noise, emissions and leaks advisory were followed by a fail in the same group at the next MOT, typically 12 months and 8,547 miles later (4,715 advisories followed).
Source: DVSA MOT bulk data (OGL v3.0) · Window: 2019–2024 · n = 4,715 (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
BMW 4 Series 2013 · BMW 4 Series 2014 · BMW 4 Series 2015 · BMW 4 Series 2016 · BMW 4 Series 2017 · BMW 4 Series 2018 · BMW 4 Series 2019 · BMW 4 Series 2020 · BMW 4 Series by postcode area · BMW 4 Series body, chassis and structure failures · BMW 4 Series brakes failures · BMW 4 Series vehicle identification failures · BMW 4 Series lamps, reflectors and electrics failures · BMW 4 Series road wheels failures · BMW 4 Series seat belts and airbags failures · BMW 4 Series steering failures · BMW 4 Series suspension failures · BMW 4 Series tyres failures · BMW 4 Series visibility failures