HI all,
I have been running my newly built RS Turbo in now for around 350 miles, nearly due for an oil change.
all is going very well, however, the idle is very strange, it hunts around but in a stable condition, it will start and rev straight to 2000rpm, then drop to 1000rpm after a few seconds, then if left, it will simply sit and every 10 seconds switch from running at 1000rpm to 2000rpm,
Its so bizarre, i have set the AFR to approx 14.7 when warm and idling at 1000rpm.
Cleaned and even swapped the idle valve with no change, the TPS was cleaned and then changed out for another one, the coolant temp seems fine, Fuel pressure is 38psi when idling and vac attached,

Whilst driving, once i dip the clutch the revs will rise from whatever they were, to about 2200 for 5 seconds or so, and then settle, sometimes it doesn't settle out.
Pulling up to a junction, the revs sit high for some time before eventually dropping, seems just touching the throttle makes the revs rise and then hold high
Its on standard OFAB and blue injectors, turbo boost is connected straight to the waste gate whilst running in, so the amal/ electric bleed valve is unplugged. Disconnecting the VSS makes no difference.
The only thing that isnt standard as such, is the turbo is a T3 turbo and not a T2, but ive not heard of this behaviour before, once its run in and covered a few more easy miles, i will get a MSD chip for the T3 and have it set up.

Anyhow, for now, im just looking for a reason why this might happen
Thanks in advance