Test Description
The exhaust system will fail the MOT if:
- Part of the system missing or excessively deteriorated
- Mounting are missing or damaged so that the exhaust system is insecure
- There is a major leak
- The system emits appreciably more noise than a similar vehicle fitted with a standard system in good condition.
Emissions
These are checked using specialised equipment, the details of the check depending on the year that the vehicle was first used on the road. Excessive smoking (checked visually) is a reason for failure.
Diesel smoke emissions are checked by using a smoke meter.