Originally Posted by Michael J Fox is Canadian
The automatic retreival system sends the delorean through time near the end.
It's hard to accept this as the explaination because Doc Brown clearly said that the crashed DeLorean disappeared because it was unstable in time. Secondly if it was retreived, where/when did it get retrieved to?
If it was retreived the same way it was from Ep1, then wherever it is now, there are still two copies of the DeLorean somewhere in that timeline.
I actually think that the writers did an excellent job in holding the story together and I can't think of any paradoxes I can poke at except this one thing. I really feel that it was the wrong DeLorean that got phase out of time.