I have been told be a local Halfords garage, where I've had my regular services done since owning a 2014 Citroen DS3, that the noise within the engine is due to a timing chain problem. DS3 Customer Services told me that it was likely to be a 'known problem', which a diagnostic test at a Citroen franchise confirmed. The car is just over four years old with 35,000 miles on the clock, but because this is not being a normal serviceable part, I wanted your view on how the manufacturer should deal with this. I have taken it further with Citroen on the basis of their comment, but I'm concerned that it's out of warranty and that I chose not to use Citroen for its services.