ULEZ - Upgrade emissions to EURO 4

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ULEZ - Upgrade emissions to EURO 4


New member
Sep 17, 2016
The Ultra Low Emissions have been implemented in Central London, and is going to be expanded to up to north and south circular roads.

All motor has to be EURO 4 compliant (2006 onwards)

Would it be possible to upgrade my 1990 Fiat and 2000 Alfa Romeo to comply with EURO 4 emissions.

My Fiat is a 126 Bis, and my Alfa Romeo is a GTV.

I suspect it is not a straightforward catalyst converter modification.


Well-known member
May 23, 2011
Norfolk UK
No, because the euro rating of your car is decided by the manufacturer when the car is first built.

You could maybe swap the whole engine from a newer car that was euro4 compliant, however you’d then need to negotiate with the DVLA to change the rating of the car, which they might not do, you might have to pay for very expensive testing processes which the dvla still might not pay any attention to. You’ve then ruined the essence of owning an older classic Alfa anyway and you’ll be out of pocket a fortune and still not be able to drive in London. I can’t imagine there is a euro4 engine capable of being installed in a 126. The euro rating is definately more than just a catalytic convertor