yep, I know the site well and following smj advice figured I'd replace them (car has well over 300k km's on it). Firstly though, I figured I would have the injectors cleaned by Bosch and then flow tested. Testing showed that most of the injectors had really erratic flow i.e the spray cutting out through much of the stray arc and not consistent, (which is pretty much what smj say is likely, I believe). Anyway, I put them back in with new upper and lower O rings, outer sleeves etc while I waited for new ones to arrive. Engine runs fine really but surely well away from optimum.
I remember reading somewhere that the injectors changed on the KG engine through the model run which if true, is a shame that its either not recorded by EKTA (?) or that my supplier didn't take any notice of it when he sent me the wrong bits (and now won't swap them). bizarre
these bad boys aren't cheap.