I bought an Audi A4 Cab 2.0ltr TDI sline (Registered November 57) in march 2009 with 3000 miles on the clock from my local dealership (Bradford Audi). By the forth week of driving the car i have had ongoing issues with the DPF (deisel particle filter). This is because so i am told that soot gathers up inside the filter and causes the filter to clog up which then the car need to be diverted to the nearest motorway to be driven at a speed of 50 or 60 mph in 5th or 6th gear only when the filter clears will the car then run properly. As it is i don't have a problem with this in general as i do regular motorway driving but not daily , the principle of the situation is that the car needs immediate attention if it does not get this the engine management light comes on which then tells me there is a fault with the engine and the turbo cuts out. I have raised numerous complaints with the dealership and Audi UK who tell me that i am not driving the vehicle correctly ,and that in order to stop this i should be driving at least 15 miles every morning at the required speed. So as i don't do this sort of driving everyday and was not advised of this at the point of sale i would be looking for a like for like vehicle or a full refund but a like for like would or should only be accepted on a sensible timscale as the dealship have advised me that it may take many months in order for them to be able to match my vehicle. After i put this information in writing they contacted me via telephone saying that they could replace the whole filter and see if that would fix it so i agreed to let them do this and so they took it away and brought it back with no FOC invoice which then asks the question have they attempted to fix it at all? but no avail i am being taken for a ride its very clear to see. I am not a great expert on engines so i am looking for as much feed back as possible as to weather i should use my own expert diagnosis and where to find those experts before i enter judgement against them anyones veiws and advice would be much appreciated as this is my last and only option. The car maybe fit for purpose in some respects but not in my case and there is no question as to weather i have been mis sold this vehicle. I have gathered some cases same as my own and as i am doing this i am finding that the individuals that have also purchased Audi's on the 07/57 (model) are having the same problem and are being told the same thing (lies). I have also found through research that it is mainly people who are buying these Audi's with out right money as no way would a finance company put up with such garbage. So you see you who are targeted have the same rights as those finance companies because believe me if my car was on finance they would have to replace it immediately in order for me to pay them the money its all the same principle and such a civil matter. And so you should resort to legal action as i feel this is the only way forward. I have even considered a part exchange at BMW as they claim they don't have the same problem. Audi have caused me great stress in my career and education and even dropping my children off to school as they failed to provide me with safe transit throughout my everyday life. I paid 20'000 (outright) for a suitable vehicle to do this and i am not going to give up no matter what untill i see some justice. wish me luck.