Hi, just joined because of a problem with my C5 2.2 Diesel estate, and HORRIFYING costs from my "local" dealers. The dash warning light reads" diesel additive at minimum level". Conversations with my local dealers start off fine, "Oh!yes, that is the additive that is injected into your tank every time you put diesel in", Ok, so whats the cost of this ? "Well depending on your RPO #, c£30 or £60", Great that's 0k(me), "ah! but there's more ! "there's also this filter, and probably an ECU, and probably another filter too may be required, so up to£800". !*!* (me), from £30 or £60, how come ? "well, the ECU can't usually be reset because the software doesn't (nearly) always work, and anyway it has a time limit life, and the filter is usually blocked, and the other filter(? not sure on this, me), is usually done at the same time. WOW!! what just happened ! £30-60 to c£800 !!!!!!!!! My car is a Jan 02, 63k on the clock, regularly serviced, NO advice on this in the owner/ service manual other than a casual comment, "should be replaced at c50k miles ", nd here I was avised to wait until the light came up as there are variations on life time. How do I get out of this ? I'm a Citroen owner, get me out of this HORRENDOUS cost ! ANYONE ? Is this the PFK ?/ RFK? topic I have been reading about ? CJ.