5 yer old c4 cactus 1.5 diesel with ad blue fault. Took 4 weeks before the dealership could check the vehicle . Now been told it needs new ad blue tank at cost of £1800. Service manager admits this is a common fault and they have vehicles in every day with ad blue faults and to raise a claim with Citroën. After a week Citroën customer services said there is nothing they can do and admit they are aware of faults with adblue system. The vehicle has only done 50000 miles and now stuck in a garage with no date for when parts will arrive. Do not buy a diesel. Do not buy Citroën.