I had the first problem (apart from recalls) with my C6 yesterday - the tyre fitter said that he had not seen it on C6 (well, had not seen a C6 at all....) but was not uncommon on C5. After a visit to garage to inflate tyre the warning light came on for front onside. I stopped and the valve simply came away in my hand. It appeared to have sheared. I asked my usual tyre fitters (the excellent A&A in Cardiff) what to do and they said I would need part from main dealer. Telephoned main dealer who had one, but couldn't fit until 20 March!!!!! I therefore bought the part (over £60!) and had A&A fit. Tyre now fine, but none of th sensors work. Unless someone here has a fix I guess it will need main dealer computer at next service. I am disappointed by a number of things here. My car is an 07 plate - for a valve to corrode in a short period of time seems scandalous. Should I worry about the others shortly following suit? How can Citroen allow a situation where a fairly fundamental piece of the car can only be replaced by a main dealer and where the lead in time is 18 days? I had a further problem that when I jacked up the car I could not get wheel off hub. No amount of pulling, cut hands and persuading with my foot would budge. In the end called AA who took 15 minutes of much hammering to get it off. A&A suggested that the steel hub had corroded against the alloy wheel. Again, disappointing. Does anyone from Citroen UK read this site? I would be interested in responses from other readers or from the company, the latter by private emailif they prefer.