The vehicle will be inspected, depending on the age and fuel type of the vehicle, to check that it meets the rules for exhaust emissions.
The MOT tester will refuse to test your vehicle if they think that the smoke test may damage your engine.
You should tell them at the start of the MOT if you think this may happen.
To reduce the possibility of damage and increase the chances of passing, you should:
- keep your vehicle maintained at all times
- have the camshaft drive belt replaced at the recommended intervals
- go for the MOT with a fully warmed up engine – it will produce less smoke and is safer to test
- not tamper with the governor settings