It happened when I got the car a few months back and someone else said the same again today.........Not guilty M'lud
However I am not baffled at why I've been asked this, there is not a hint of carbon residue to be found in it.
Must be running very frugally but obviously not too lean I'd hope. Any other Sigma users found this?
As an aside, first time out in it for a few months and a super Autumn blat has just been had!!
