> those old cars will require testing and modifications (as is already the case). No they don't, that's not the case. Example: Skoda Octavia 1 TDI does not hav

> those old cars will require testing and modifications (as is already the case). No they don't, that's not the case. Example: Skoda Octavia 1 TDI does not have DPF and nobody is retrofitting DPFs into those cars.