is it still possible to die from carbon monoxide fumes from a car in an enclosed space,or have catalitic converters made the fumes safer,like i said a very dopey question

Only one way to find out

the core of some older ceramic cats can break down quite badly, in which case yes. a quality metal cat should leave you dying of boredom.

Is there not enough other stuff in the smoke to kill you in an enclosed space?

no, it's not possible with a modern car (petrol or diesel).

I'm interested as to why you're askign though?

no, it's not possible with a modern car (petrol or diesel).

Of course it's possible. Carbon Dioxide will kill you just as effictively as Carbon Monixide as you are displacing the oxygen, (has to be within a few percent of 21) with a gas, or more correctly a mixure you can't breathe.