The problem is, the legal owner of a car can't steal it. If he put her name on the title, he gave her a gift of the car. So, in order for him to have ANY recourse, he has to be able to prove that she did something that is not just morally reprehensible, but legally wrong. It's not wrong to accept a gift. It IS wrong to trick someone into giving you a gift - that's financial elder abuse, which is a crime. Or if they had an agreement that he would put her name on the car if she drove him to doctor's appointments, and she vanished, then he could sue her for breach of their oral agreement.
The problem is, California police can't arrest her on the east coast, and one misdemeanor count of elder abuse isn't the type of thing they'd normally extradite for. He can file a lawsuit against her in California, but if she doesn't have any assets in California, that's not terribly helpful. To collect a judgment against someone who lives in another state, it's necessary to file the judgment in that state and get a new court order before he can start collecting. He'd probably have to hire a lawyer to do that, considering the time and expense of travel, plus the toll on his health if he's already not well.
If the father's name is ***** ***** the car, he may want to consider hiring a private investigator to help him locate it. Once he knows where it is, he can take it back. Or, he could try sending her a demand letter, via certified mail, giving her an opportunity to return the car (or tell him where it is - he can get a key from the dealer with the title and registration) in order to avoid a lawsuit. She might take the letter more seriously if it comes from a lawyer. It's possible that she would give it back if she thinks she can't get away with keeping it, especially if she's at all concerned with her credit.
But the main thing you have to keep in mind is that, if he's suing, he has the burden of proving that his daughter committed a legal wrong. Which means he has to prove that the car was NOT a gift, that they had an agreement, and that she broke it. Without something in writing, that's difficult (although if she doesn't show up in court, he'll win). Any type of writing will do, if she admits they had a deal: emails, texts, tweets, Facebook messages, anything at all, as long as she admits it. Or if he had a third party who overheard the conversation. But he has to show that she made him a promise and that she broke it. That's the only way to get a judgment.