Speed Jet, You have all the right to cancel a car after you have booked and before you take delivery. The maximum you might lose is a small sum say 10% of advance or some amount written on the booking agreement you signed. No one can refuse you your money. In you case, since the car is not passing the PDI they have to return the entire amount. Wait for couple of days and then let them know that you are cancelling and ask for complete refund.