Cars sold at auction are sold on the auctioneer's description, not the catalogue description. The auctioneer's description is always taped in case of any dispute. Often at a classic sale when something like this happens, the condition of the car is clarified by the auctioneer.

If the auctioneer stated that the car was running when it arrived at the sale, but subsequent attempts had failed to persuade it to run, then that would have affected the bidding and it may well be that your successful bid was £100,000 less than someone else might have bid had the car been running.

So, first step: go back to the auctioneers and ask for a copy of the auctioneer's description at the sale. If he described it as running, then you have a clear-cut dispute. if he didn't (or if he did), you have to decide if the likely cost of getting the car running warrants getting the work done. It may be that Aston Martin will contribute. Which car is this? Can't be the DB2 coming up in Bonhams at the Festival of Speed. Was it the Spectre DB10 sold by Christies for $3.7 million?