mechanics.tradeExhaust system: has a major leak of exhaust gases
This was recorded 244,124 times on cars and light vans in 2025, which makes it number 37 on the list of things that stop a car passing.
244,124recorded in 2025
37on the national list
1.2%of the top forty defects
What the tester is looking at
Exhaust system leaking or insecure
What you can do about it
A small leak is often a quick weld or a clamp.
How serious it counts as
The tester records this as a major defect. What the categories mean.
All forty defects, from 42,728,066 MOT tests in 2025.