In article ,
The Natural Philosopher wrote:
The MOT doesn't test CO and NOx, yet!

Does test CO...IIRC

Don't have a diesel, but a petrol MOT gives (or once did) you the standard
'four gas' readout from the testing machine.

CO, CO2, NOX and hydrocarbons, IIRC, as percentages. Generally, if the CO
is within spec, the others will be too.

--
*Reality is a crutch for people who can't handle drugs.

Dave Plowman London SW
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