You can, but to win ridiculous cases you need massively out-lawyer the defendant. It's a lot easier for a big company to out-lawyer a handful of individuals than the other way around.
VW got fined for that, not enough though and many others got out scot-free for similar rigging. A handful of cars (within regulations) don't pollute enough to cause harm but throw in thousands and thousand on narrow city roads and then do we blame the city planners?
