not all old cars are "bangers" like the BBC want us to believe

So why did Saab fit CAT from 1990? Obviously, there was there was a common EU/US design spec.

And an enormous marketing campaign. There's quite a lot of cars from then that had cats, as they where obligatory from 92 so if you where making small numbers then it made sense.

So? Clean technology was good for marketing. It was the bleeding edge at the time.

johannes gurgled happily, sounding much like they were saying:

Not quite. As with ABS, they were optional for '90 and standard for '91. Obviously, there was there was a common EU/US design spec.

No, there was a very powerful precious metals lobby which managed to get them to be required, hugely increasing the demand for platinum.

johannes gurgled happily, sounding much like they were saying:

Three-way cats were hardly "bleeding edge" when they were introduced in the mid '70s.

The whole idea that a modern Euro 4 car is superior green and clean is nonsense. Try breathing in the exhaust and see what happens...

Cleaner petrol probably accounts for a lot, but that of course affects both new and old bangers.

And why do brand new quality diesel cars emit a black puff of smoke when jumping on the accelerator. I've seen that from merc's.

johannes gurgled happily, sounding much like they were saying:

All diesels will puff smoke on hard acceleration - it's an inevitable result of the over-fuelling necessary to make full power from a diesel.

It'll stink, but it'll still be cleaner than Euro 1

Cleaner petrol will make very little difference to NOx & CO