 Problem with 2nd hand car hours after buying. HELP!
Right, its a long story so here we go. I went with my sister to go look at a second hand audi a3 from a trader on monday. The car is a 04 plate Audi A3 2.0 Tdi. Described as one owner from new, excellent condition, driving fine etc, years mot plus a fresh service from the garage. HPI came back clear, the v5 was present and they even included one months warranty on the car.
We agreed to pay the asking price of £10,990 and left a £200 deposit, with the car to be picked up on the following day. We arrived the next day to pick up the car, paid the rest of the payment via switch and were on our way. About 10 miles from the garage the car decided it didnt want to go above 50mph. My sister who was driving, pulled over and let me take the wheel. The car drove fine for me until it did the same thing of not wanting to above 50mph a few miles further. I called the garage, they told us to come straight back and they would sort it.
We returned to the garage, they put the car onto their diagnostics machine and said it needed a new map sensor. They supplied one and fitted it all under the warranty and also increased the one months warranty to 3 months. We set off home for the second time. This time I drove the car back. 20 miles after setting off, the car encountered the same problem. I rung the garage again and they told me to nurse the car back home, and either they would come and collect it the next day or I could book it into my local audi dealer who would sort the problem and bill the trader I purchased the car from.
I decided to get it home and ring the local audi dealer. The car was booked in for today. I recieved a call a few hours after dropping the car off telling me that the turbo had failed and it required a new unit, which was over £1k + Labour and VAT. I then recieved a call from the trader stating he was going to pick the car up and have it repaired elsewhere, but still foot the bill. I told him I would rather return the car to him under section 14 of the sales of good act, and get a refund. He declined and now im in this dilemma as he is wanting to repair the car and foot the bill and refuses to refund me the £10990 we paid for the car which isnt fit for its purpose
Am I legally entitled to ask for a refund or do I have to let the trader repair the car first? TIA | 
