MOT defects: Catalyst emissions

Noise, emissions and leaks

14 defects: 14 major. 2 can be given as an advisory instead.

Certificate wording	Severity	As an advisory	Inspection manual
Catalyst emissions emissions likely to be affected by an exhaust leak	major	None	An induction or exhaust leak that could affect emissions levels
Catalyst emissions emissions likely to be affected by an induction leak	major	None	An induction or exhaust leak that could affect emissions levels
Catalyst emissions carbon monoxide content after 2nd fast idle exceeds manufacturer's specified limits	major	None	Emissions levels exceed the manufacturer's specified limits
Catalyst emissions hydrocarbon content after 2nd fast idle exceeds manufacturer's specified limits	major	None	Emissions levels exceed the manufacturer's specified limits
Catalyst emissions carbon monoxide content after 2nd fast idle exceeds default limits	major	None	Emissions levels exceed default limits
Catalyst emissions carbon monoxide content at idle exceeds default limits	major	None	Emissions levels exceed default limits
Catalyst emissions carbon monoxide content at idle exceeds manufacturer's specified limits	major	None	Emissions levels exceed default limits
Catalyst emissions hydrocarbon content after 2nd fast idle exceeds default limits	major	None	Emissions levels exceed default limits
Catalyst emissions Lambda reading after 2nd fast idle outside specified limits	major	None	Lambda coefficient outside the default limits or the range specified by the manufacturer
Catalyst emissions emissions - engine idle speed too high	major	None	The engine is idling at a speed clearly above its normal idling speed
Catalyst emissions emits dense blue smoke at idle	major	None	emits dense blue or clearly visible black smoke for a continuous period of 5 seconds at idle
Catalyst emissions emits visible black smoke at idle	major	None	emits dense blue or clearly visible black smoke for a continuous period of 5 seconds at idle
Catalyst emissions emits clearly visible black smoke during acceleration	major	emits black smoke during acceleration	emits excessive dense blue or clearly visible black smoke during acceleration which would obscure the view of other road users
Catalyst emissions emits excessive dense blue smoke during acceleration	major	emits blue smoke during acceleration	emits excessive dense blue or clearly visible black smoke during acceleration which would obscure the view of other road users

Pre-2018 names for this part

Catalyst (10)

Other parts in Noise, emissions and leaks

All Noise, emissions and leaks defects

Dabers ANPR shows the full MOT history, defects included, for the car in any photo. How it works

Add to Chrome

Contains public sector information from the DVSA licensed under the Open Government Licence v3.0.