Hi All Thanks to all that have replied to this post and those who visited the NGK stand. It now seems that the problem has been a case of wrong application due to Misprints ,When fitting plugs in future we will be double checking our info.But who has the right info? Even now we are fitting higher spec platinum plugs to vehicles especially Fords to cure misfire problems when all our info says different, Never mind at least we now know always check plugs FIRST Regards Tony