Oil leak MOT advisory: what it means and which cars get it
In DVSA MOT data for 2023, analysed by RegTail, testers recorded this as an advisory on at least 4.0 in 100 initial MOT tests. The Vauxhall Vectra got it most often: recorded 18.8 times per 100 of its 39,116 tests.
DVSA wording: Fluid leaking excessively and likely to harm the environment or to pose a safety risk to other road users.
What it means
Engine oil is escaping, usually from a gasket or seal such as the rocker cover, sump or oil filter. As an advisory it usually reads "Oil leak, but not excessive": the tester has seen oil, but not enough to fail.
How serious it is
A major defect, so a fail, when fluid is leaking excessively and likely to harm the environment or be a risk to other road users. The manual's guide is a pool more than 75mm across within 5 minutes. A continuous leak that is a serious risk to road safety is dangerous.
Source: MOT inspection manual for cars and light vans, section 8.4.1.
- Dangerous FailA direct and immediate risk to road safety or has a serious impact on the environment. Do not drive the vehicle until it's been repaired.
- Major FailIt may affect the vehicle's safety, put other road users at risk or have an impact on the environment. Repair it immediately.
- Advisory PassIt could become more serious in the future. Monitor and repair it if necessary.
What fixing it usually involves
Depends on the source: a gasket or seal can be a small job or a large one if the engine or gearbox has to come apart. Check the oil level regularly in the meantime.
A general guide, not a quote: ask a garage to inspect the car.
Which models get it most
Per 100 initial MOT tests on each model, among the 185 models with at least 20,000 tests where it is among the 40 most common items. DVSA MOT data for 2023, analysed by RegTail.
| Model | Tests | Advisory |
|---|---|---|
| Vauxhall Vectra | 39,116 | 18.8 |
| Vauxhall Antara | 22,582 | 18.0 |
| Peugeot 206 | 58,647 | 17.6 |
| Peugeot 207 | 159,030 | 16.2 |
| Peugeot 307 | 39,404 | 13.9 |
| Vauxhall Zafira | 229,031 | 13.7 |
| Saab 9-3 | 43,277 | 12.8 |
| Vauxhall Astra | 704,979 | 12.3 |
| Citroen Dispatch | 52,335 | 12.1 |
| Vauxhall Meriva | 101,694 | 11.7 |
What to check at a viewing
- On the carLook under the engine and at the ground where the car was parked for fresh oil, and at the engine for wet, dark grime. A freshly steam-cleaned engine bay can hide a leak.
- In the MOT historyIf this appears as an advisory, see whether it came back at the next test or turned into a failure, and ask the seller for the receipt if it was fixed.
Check a specific car
Fleet averages only go so far. Enter the registration to see that car's own MOT history, mileage record and current condition, free.
Questions
What does "Oil leak" mean on an MOT?
Oil leak: is it an MOT fail?
Which cars are most likely to get "oil leak" on an MOT?
More engine, exhaust and leaks defects
How these figures are made. We counted the defects recorded at every initial MOT test (not retests) of cars and light vans in Great Britain in 2023 in the DVSA anonymised MOT dataset, 33,842,940 tests in all. Each item counts once per test. A failure is a major or dangerous defect, including one fixed during the test. A model's rate is the share of its tests where the item was recorded.
For each model we keep its 40 most frequent items, so a model where a defect is rarer than that is not listed, and figures for all cars are a floor. Defect names and explanations are ours, checked against the MOT inspection manual; DVSA's own wording is shown under each name.
Contains public sector information licensed under the Open Government Licence v3.0. RegTail's analysis of the DVSA anonymised MOT dataset, 2023 tests.