Do ALL the modern cars nowadays have catalytic converter fitted?
Most of the world now has emissions regulations which cars with petrol (gasoline) and other spark-ignition engines can only meet with catalytic converters. There may still be some emerging markets where there is no requirement as yet – perhaps some of the southern former-soviet states such as Azerbaijan, or some African countries. Diesel engines can meet some less-stringent emissions regulations without them, and their action is slightly different.
