Lauryn this happened to my Arosa 1.4 TDi in December. Seat wanted £600, then vat on top, then labour on top of that so i kindly told them where to go. I took my car to a company called ES ALternators in Kirky. The guys had the car and ECU for a week and found that one of the small circuit boards inside was cracked. They guys sorted that out, drove the car for a road test, full diagnostics then told me to road test it before i took it away then ran a full diagnostic on it beore i left to give me the print out as proof. All in all - £330 in VAT. Guys were top class and really know there stuff. A big diference from SEAT wanting around £1000! 0141 776 3689 Hope this helps