So it would seem valve issues are common then, am I right in thinking though that valve problems would produce symptoms (excluding todays experience obviously) and be more predictable??

Lee, I think your suggestion regarding swapping injectors is probably the best next step, if the fault stays on cylinder 3 then I'm gunna have to wait for it to misfire again in order to inspect things further!

James, interesting concept for cat saving, makes diagnosing faults difficult though dunt it!!

Thanks everybody
Craig