Does the little red light on the fob light up when you press the lock/unlock buttons?? If not and you have a new battery then the most likely situation is that the battery holder in the fob has snapped...easy enough to weld but you will often find its just held in place by a piece of folded paper...which of course can shift...
As the misfire is on no 6 which is the one with the knackered lead I would say change the lead, clean up the plug and see if that gets rid of the misfire...
If you can head over here I can stick the computer on it and reset old codes etc...
As for the chip/immobiliser, if you can start the car then the code is old...if it was current then it just wouldnt work!
Thanks for the offer. i may take you up on it
The keyfob remains in-op as it was only the car battery that was changed.
Mines the later 2.6, so no leads as such, but the sleeve / shroud for pot 6 is quite damaged, and that (I think) is likely the root of the problem. Just looking after the little 'un (and trying to work) whilst the wife has nipped out for a couple of hours. After which I'll have the coil packs out.
If I was to run a bead ofsilicone sealant around the edge of the dis-pac, (where it got damaged removing it), I assume that that would be sufficient to keep it water tight? Would the silicone sealant cause any problems with the heat soak it will suffer?