idling problem

[bloomers76]

hi, i have a 1996 e36 318 is coupe m44 engine.
i have had a idling problem for a while now and it has come to the mot and it has fail it's emissions test at high idle. i have replaced the lamba sensor, ecu, air mass sensor, complete inlet manifold with all the sensors (TPS, ICV) and replaced the inlet manifold gasket and still the problem persists.
i have connected a vacum to the inlet to check for air leeks and there are none.

don't know where to go from here can any one help, can post video if it helps.