My beloved C30 does 600miles a week. 120 round trip commute. I had heard about cars not running because the filter blocks up, in the city as short journeys, low revs, the engine never cleans. I do travel at about 60mph to get 60mpg from the car and quite a bit at 54 due to average speed cameras and road works, never thinking this would happen to me! The engine would rev round to 1600,about the same speed as if I was doing 54mph. The dealer has regenerated the filter £400, the cost of removal was 500 Replacement was 1000. Have I done the right thing? Could this really have happened and will it happen again? Best option... Removal replacement drive faster? Are there cars without this device? Thank you for all your advice over the years which I have followed but the first time I've had to write in myself.