I purchased a 2 year old 19,000 mile car from a large car supermarket 3 weeks ago and drove it 50 miles home. The car would then not start (after 1 hour of ownership) and was towed to the local main dealer and has been there ever since. The main dealer believe the problem is contaminated fuel, but can not confirm whether this was the small amount of fuel in the car when purchased or the fuel I put in immediately after purchase (I put in the correct fuel and the receipt to prove it). They now say it is not a warranty issue due to it being a result of outside interference and so want to charge me to get the car back (saying all they want to do is repair the car and get the money, washing their hands of the issue) . I have been pushing the car supermarket to exchange/refund me for the car as it was not fit for purpose, but feel they may try to deflect the situation on to the petrol station (who I believe are unaware of the issue). I do not want to pay the dealer as I feel I may end up out of pocket by the £1700 repair bill through no fault of my own as the place of purchase and the fuel company end up in a stalemate with neither accepting liability. Am I correct in saying the liability is with the place I bought it (and I should just insist on my money back) and the onus is on them to prove someone else is liable and reclaim damages if they can? Thanks