Mg zs idle/surging

Hi guys, new the fold with an mg zs 180 it's done 150k but has been fantastically looked after!



Trying to fix it up after it failed MOT.



I've sorted a number of issues, however am left with 1 tricky issue...



The car Idles all over the shop, when settled it idles at 1500rpm... But will surge/hunt between 1800 -> 2100 rpm when throttle is touched.



I've gone through a checklist like this



Replaced TPS with a known working TPS

No difference

Removed all inlet sensors and breather pipes and cleaned them... Including the ICAV.

Again no difference.

Checked all wiring relating to inlet/throttle and nothing rings any alarm bells.



Upon disconnecting the ICAV and having the car run it still idles HIGH but does NOT surge or hunt



I have covered both the throttle body intake and ICAV intake (small inlet above large/main body) the car carrys on idling around 1200 rpm. In my experience the car should struggle to run??? Or stall???



This leads me away from the throttle stuff and onto leaking inlet manifold gaskets? They are BGA ones I replaced a week ago after a thermostat change.



Please find the time to suggest my next step or give me some advise.



All help is much appreciated.



Thanks

from the last news http://ift.tt/1kYOigw

via IFTTT