Sp6 erratic idle

[willmo]

My Sp6 idle is erratic - lumpy tickover especially when cold. Problem seems to go away at higher revs and when warm, although even then it's not perfect on idle. I have had it hooked up to laptop and checked over by Racing Green who changed the lambda sensors but it's still bugging me. Not in a hurry to go spending any more until I can understand what the cause is.

[natben]

Could be that the throttle bodies need balanced, there is six of them and if they are not aligned then you can get erratic idle but I'm sure RG would have checked before they went replacing items. So might be something completley different