Only if it's excessive: fluid leaking enough to harm the environment or be a risk to other road users fails, and a continuous leak that's a serious risk to road safety is a dangerous defect. A smaller leak can be noted as an advisory.
Testers grade each defect: a major or dangerous defect fails the MOT, a minor one passes but is written on the certificate.
| Defect | Result |
|---|---|
| Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users | FailsMajor |
| Fluid leaking continuously and likely to pose a serious risk to road safety | FailsDangerous |
From DVSA's MOT inspection manual for cars and passenger vehicles. Contains public sector information licensed under the Open Government Licence v3.0.
In 2025, 38,328 car MOTs failed on an oil leak: 0.12%, or about 1 in 820. 6% of those failures were for a dangerous defect. Testers also noted it as an advisory on 1,604,783 MOTs: something to keep an eye on that didn't fail the test.
Share of the MOTs that failed on an oil leak. One MOT can fail for more than one reason.
Share of car MOTs in each mileage band that failed on an oil leak.
0.34% of MOTs on cars registered in 2005 failed on an oil leak, against 0.01% for cars registered in 2022.
Models that failed on an oil leak at least 1.15 times as often as the average car of the same age and mileage, out of 71 with at least 30 MOTs failed on it.
Least often: Toyota Auris (0.1×), Toyota Yaris (0.2×), Honda Jazz (0.3×), Honda CR-V (0.3×), Honda Civic (0.3×).
Only if it's excessive
In 2025, 38,328 car MOTs failed on an oil leak, about 1 in 820. 6% of those were rated dangerous.
1 in 820car MOTs failed on an oil leak in 2025
Only if it's excessive: fluid leaking enough to harm the environment or be a risk to other road users fails, and a continuous leak that's a serious risk to road safety is a dangerous defect. A smaller leak can be noted as an advisory.
In 2025, 38,328 car MOTs failed on an oil leak: 0.12%, or about 1 in 820. 6% of those failures were for a dangerous defect.
Against the average car of the same age and mileage, the MG ZS (3.1 times as often), Vauxhall Mokka (3.1 times as often) and Vauxhall Corsa (2.8 times as often), going by 2025 MOT results.