Oil leak advisory missing from MOT before buying secondhand car

[Emsy999]

Hi all,

I bought a secondhand car in November 2024. It was due an MOT three months after I was due to purchase it so I asked for the dealership to carry out another MOT before I bought it. They did and it passed with no advisories.

I bought the car and had no issues. Fast forward to November 2025 and it had it's annual MOT. An oil leak problem appeared as an advisory. I've spoken to my trusted mechanic and it's going to be a big job (they think it's behind the gearstick so will be £1k+ to fix it). I've since looked back at the MOT history and the same advisory (word for word) appears on previous MOTs. I've done some research and some places say that MOT advisors are permanently logged for the registration but then other places say that it depends on the tester as to whether they include it.

Which is it? Is it permanently logged and if so why didn't it appear on the MOT when I bought it? My mechanic has implied that the dealership might have done me over and had it removed so that I bought the car but surely the MOT tester wouldn't chance this.

Where do I stand with this? Is there anything I can do?

Thank you!

A previous advisory does not automatically have to appear on every later MOT. The tester records what they can see on the day, so if the leak was cleaned, not obvious, not dripping badly, or judged differently, it may not be listed that time. That said, if the same oil leak appeared before you bought the car and then appeared again word-for-word later, I would definitely be asking questions.
The first thing I’d do is get your mechanic to write down exactly where the leak is coming from, with photos if possible. “Behind the gearbox” could mean rear main seal, sump area, gearbox input area, or oil running from higher up and collecting there. Before arguing with the dealer, you need a clear diagnosis and evidence that it is an old leak rather than something that developed after purchase.

I would then write to the dealership with the MOT history, the current advisory and the mechanic’s report, and ask why the previous advisory disappeared on the MOT they arranged before sale. Don’t accuse them straight away; ask for their explanation and whether they are willing to contribute to the repair.
If parts are needed, it may also help to compare prices for related items such as an oil pump or other engine oil system parts before accepting a £1k+ quote, but the exact leak source needs confirming first.

Realistically, because you bought the car a year ago, it may be harder to reject it now. Your best angle is evidence that the fault was already known or present before sale, especially if the MOT history supports that.