hi I own a 2008 a3 170 with dpf filter I only do 4 miles to and from work every day and filter light came on,couple of days later car went into limp mode and had to take to audi garage and have dpf regen at a cost of £60 but this can only be done 3 times but would rather avoid, any ideas as very rarely go on any long journeys and don't want to go round reving nuts off it just to burn filter clean any help thanks martyn