After about 30 minutes of digging through Ebay rules, I
think I know what is happening to the auctions.
Ebay doesn't make it easy to read their rules, they scatter them all over, but this one looks like the one that is shutting down the auctions:
http://pages.ebay.com/help/policies/pre-sale.html
Ebay prohibits "Pre-sale Listings," those that advertise the sale of items that are not in the control or possession of the seller at the time of the listing."
The exception is if the seller seller guarantees that the item will be available for shipping within 30 days from the close of the auction.
It doesn;t look like a vehicle can be offered on ebay before it is at least bucked.
Keith