Hi Sean, et all,
I have been busy the last couple of days & missed these extra issues.
In reply to Kevin's post you say the timing belt tension seemed ok but was it spot-on or on the loose side of right? i.e could it possibly have jumped or not? was it the O/E belt & tensioner from factory or had it been changed & possibly incorrectly timed/tensioned?
Alan could be spot-on with some sort of damage & the ECU is trying to smooth out but unable to do so within a reasonable set of limits (therefore at stop) assuming that the cam had possibly nipped up & caused the belt to jump, could you remove the caps one at a time to inspect for damage & if no damage, then what about timing it up correctly & carrying out a compression test, looking especially carefully at the first couple of compression strokes on the gauge to see what each cylinder can produce instantly rather than what it can build up to with several more compression strokes, if then in doubt a compression-loss test to identify possible issues before removing the head?
I must admit that Alan was thinking on his feet a far more than i was here, it not unusual to see another cylinder backing off fueling after a large + reading, but i guess should normally be the next cylinder in firing order so i should have thought it through a bit further, sorry.
You could always have swapped injectors around yourself to prove before buying a new one, but you must have had also other doubts if you went on to check timing first, just as well you did or i might have been recieving your invoice by now!.
Phil.