1yr old dog ate a toy plastic car has been throwing up yellowish light brown
With some plastic in it been about 3 days she is eating drinking okay pooping regulary just throwing uo

Sounds like there might be a small blockage by the gag reflex. The only thing you can do is take her to the vet and see if they can see it with an x ray or hope it passes and doesn't cause and tearing in the throat or stomach lining
. If it were my dog, I would have been at the vet 3 days ago.