I'm seperated from my wife for over 8 monthsShe has my car . That is in my name only. Can I get it back and how?

A Divorce Court judge can order possession of a marital asset, nobody else. If the car was purchased during the marriage, and paid for out of your income, it's marital property. It's 100% legally irrelevant whose name is on the title, loan, etc. That doesn't mean a judge can not decide to let you have the car, but until then, it's marital property. On top of that, in most cases a judge will order "status quo" until a final hearing. That means if she's had the car for eight months and you've been paying, she may well keep it, with you paying, at least until the entry of a final Divorce.