Identity and Object

Here is a philosophical problem concerning objects and identity:

Imagine you have bought a new car and visit me at my house. When you come inside you move to the window and point at your car and say "that is my new car". After coming to the window and appreciating the beauty of your car, I invite you to the kitchen where we sit down and eat and chat for three hours.

During these three hours, some philosophers who also happen to be good mechanics replace every single piece of your car with an exactly identical piece. The only piece they choose not to replace is the locking system so your switch would still work.

You leave after coffee and sit in your car, start it and drive away. While you are driving, one of the philosophers calls you and tells you about what they have done to your poor new car. Some questions pop up naturally: Is that really your car? If your answer is "yes" then "why do you think so?". If not, where is your car now?

Incidently, I lied about the locking system. In fact they even replaced the locking system with an exactly identical one.

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Well, i haven't been writing for sometime so it had to be something crazy. I may extend this posting in future.