Se eu tentar escrever

Car myCarObject=getCar();
Intent details = new Intent(Start.this, DetailsCar.class);
                details.putExtra("Car", myCarObject);
                startActivity(details);

Eclipse me mostre um erro de compilação"O Método Put Extra é Ambíguo para o tipo Intenção" na linha

  details.putExtra("Car", myCarObject);

Se eu usar o código

Car myCarObject=getCar();
ArrayList<Car> parcelableExtra = new ArrayList<Car>();
                parcelableExtra.add(myCarObject);

Intent details = new Intent(Start.this, DetailsCar.class);
                details.putExtra("Car", parcelableExtra);
                startActivity(dettagli);

E eu tento carregar o extra com este código no destino Intenção com

ArrayList<Car> parcelableExtra = new ArrayList<Car>();
        parcelableExtra = (ArrayList<Car>) getIntent().getExtras().getParcelable("Car");
        Car c=parcelableExtra.get(0);

Eu recebo este aviso

12-14 05:30:07.669: W/Bundle(19823): Key Car expected Parcelable but value was a java.util.ArrayList.  The default value <null> was returned.
12-14 05:30:07.679: W/Bundle(19823): Attempt to cast generated internal exception:
12-14 05:30:07.679: W/Bundle(19823): java.lang.ClassCastException: java.util.ArrayList
12-14 05:30:07.679: W/Bundle(19823):    at android.os.Bundle.getParcelable(Bundle.java:1106)
12-14 05:30:07.679: W/Bundle(19823):    at my.app.com.DetailsCar.onCreate(DetailsCar.java:43)
12-14 05:30:07.679: W/Bundle(19823):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
12-14 05:30:07.679: W/Bundle(19823):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
12-14 05:30:07.679: W/Bundle(19823):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
12-14 05:30:07.679: W/Bundle(19823):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
12-14 05:30:07.679: W/Bundle(19823):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
12-14 05:30:07.679: W/Bundle(19823):    at android.os.Handler.dispatchMessage(Handler.java:99)
12-14 05:30:07.679: W/Bundle(19823):    at android.os.Looper.loop(Looper.java:130)
12-14 05:30:07.679: W/Bundle(19823):    at android.app.ActivityThread.main(ActivityThread.java:3687)
12-14 05:30:07.679: W/Bundle(19823):    at java.lang.reflect.Method.invokeNative(Native Method)
12-14 05:30:07.679: W/Bundle(19823):    at java.lang.reflect.Method.invoke(Method.java:507)
12-14 05:30:07.679: W/Bundle(19823):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
12-14 05:30:07.679: W/Bundle(19823):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
12-14 05:30:07.679: W/Bundle(19823):    at dalvik.system.NativeStart.main(Native Method)
12-14 05:30:07.679: W/dalvikvm(19823): threadid=1: thread exiting with uncaught exception (group=0x40018578)

E o aplicativo falha com uma exceção de ponto nulo

Meu objeto Car é parcelável

então .... o que está errado?