I always thought the car was a kind of barrier, put there deliberately to prevent an enemy from ramming through the gate (or chain) and proceeding further. If you look closely at that wrecked car, I believe you'll see that the doors appear to have been removed cleanly and deliberately, not as a result of a real accident.
Ntra la porta tua lu sangu � sparsu, E nun me mporta si ce muoru accisu... E s'iddu muoru e vaju mparadisu Si nun ce truovo a ttia, mancu ce trasu.