Hi mate - yes Filter is reasonably new. The det issue is very very familiar to me - I suffered with it for quite a while before Stu solved it with the map. It is not the usual sound that is associated with det (ie traditional pinking) - it is hard to describe. The car runs exceptionally well - which is not consistent with a car that is detting its tits off. I can only assume that the problem is localised to a single cylinder, and in very specific conditions. Either that or I have super human hearing (which I dont!)


I have a friend with a rolling road. I may have a play with his at the same time, though in my experience, the ambient noise usually ruins the gains.

I agree with you about ruling out poor fuelling - this should be easy to eliminate though - I will put the reliable Wideband Lambda on it once I have corroborated the figures for the pressure regulator (again this should rule out the filter if it is blocked then it will not allow the regulator to see the requisite fuelling), I will run her to see what the air fuel ratio is. If it goes a little to lean, then I will have my answer I guess.