When we pull up at the lights our mondeo revs on for a bit then settles down to a normal idle.
Looked at the net and changed idle control valve. Next step is to look for a split hose.
Question is am I looking for a suck or a blow?
Try spraying some carb or brake cleaner on vacum/breather hoses with the engine idling . Listen for a change in engine note and note where you’re spraying , this is where the air leak will be if there is one .