What do the different letters after Euro 6 mean?

I have looked at two identical cars of a similar age but when you go on the DVLA vehicle check site they have different emissions. One is registered May 2019 has CO2 113g/km and euro status EURO 6 W. The second one is August 2019 but has CO2 of 120g/km and is EURO 6 AG

I'm guessing it's something to do with the EURO 6.2 thing I keep coming across which seems to have mandated the fitting of a GPF to pretty much anything direct injection but I can't seem to find a definative answer as to the exact dates. I'm hoping the May 2019 car might have been built before this came into effect and was just not registered until afterward so does not have one fitted and there was a kind of "grace" period which meant these cars could still be sold without having to be modified by the manufacturers.

Asked on 21 March 2024 by Mark Carpenter

Answered by David Ross
The letters you describe do relate to specific level of conformity to emissions standards. Unfortunately it is a very complicated system, because the letters W and AG reflect the vehicle's emissions standards in respect of the vehicle's certificate of conformity, whereas the emissions standards used for low emissions zones use a different series of letters and numbers. As an example, Euro 6 AG translates into Euro 6d-TEMP, which was is a standard for vehicles for new type approvals from September 1st 2017 but for already homologated vehicles until September 2019.

Unfortunately this does necessarily mean that the May 2019 car does not have a gasoline particulate filter as these were introduced in 2016, and became a required part of EU compliance in September 2018.
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