Hi Kyle,
I think you meant "corroded" but anyway - I would agree that most of the car would be rotted away, certainly the wooden coachwork and wheels would have been gone by 1915, perhaps even the body itself is gone, but fragments of the body and perhaps the leather upholstery may remain. Certainly the bare frame itself complete with axles and engine block would have survived 91 years down there, having been cast from steel and iron. Now whether it was forcefully smashed to bits and ejected from the holds when the ship hit bottom is another matter, judging by the devastated Grand Staircase remains I doubt anything in the cargo holds fared any better.
Best Regards,
Brian