Won't idle when warm

[newuserhere]

Car: mk2 (54) focus; 1.6l petrol

Problem:
When cold rough on idle
When warm cuts out when falls to idle
When warm sometimes won't start without foot on throttle. If it does start it will hit about 900rpm then fall until cuts out
I can hold foot lightly on pedal and although a tad rough holds fine. If I rev up it runs smoothly and nicely! Can rev to red line spot on.

I've looked at live data and voltages seem to change for pedal position and throttle butterfly position between pressed and not pressed. Although whether they are reading correctly or not I don't know.

I bought it with timing slip. Put 8 new exh valves in and the works. Although that's a common problem on these it seems.
I don't think it's related though as it wouldn't run smoothly when revving if there was engine problems.

Any ideas?

Edited by newuserhere on Thursday 17th November 16:47

[newuserhere]

It's a different engine with electronic throttle body. Tried cleaning that no difference

[newuserhere]

Also had breather pipe off no splits

[newuserhere]

Plugs have been changed. Checked gaps today also.

I have a mk1 1.6 focus so switched all Ht leads and coil pack across and no different.

Gonna see about the throttle body next.

Map pressure seems to spike with revs dropping

[newuserhere]

The rocker Breather entered inlet before butterfly valve

[newuserhere]

Nah that's not my issue. Even if split it's just drawing in unfiltered air in the same way as it does from filter. Map pressure is still controlled by the ecu/throttle body