I bought a used Jaguar XF from a garage a year ago and it has just failed its first MoT since I've owned it. On investigation, it turns out that the Diesel Particulate Filter has been removed at some point and the engine control unit hacked to ignore the missing DPF. The garage I bought the car from is claiming it's not their responsibility as the car passed an MoT before they sold it, however I was of the understanding that it's been illegal to sell a car with the DPF removed since 2014.

What are my options? I had to spend £450 at a diesel specialist to determine the filter was removed and now face a bill of thousands to make my car roadworthy again. Surely the garage has a responsibility to repair my (illegal) car? If they had an MoT performed last year and it passed despite a missing DPF then surely that's something they need to take up with the MoT centre, not pass on to me?