Some help needed please

[wakeyboy81]

Hi guys i am new to fords and have a few questions please.

Firstly my car is a ford mondeo mk3 2005 2.0ltr auto petrol.

First question

I had the inlet manifold flaps sorted as i didnt know when bought it was an issue and it was also revving at around 1500 rpm on tickover. It's all been swapped now and for 30 miles was great. When i got home the reving started again. I also at the same time had the oil return pipe replaced at £43 from ford dealers. All was good then it acted up again reving. This morning i started it and now its fine again ??? anything  i should be looking for. Also the guy that did al lthe work seems to of left a pipe off i am not sure what it is its a thin pipe that looks like it comes from the top of the auto box not sure if it should just be loose nothing leaking from it has a tiny bit of suction if i put it up to my mouth i can just feel it should this be loose or connect to something. Its the pipe that goes to top of waht i believe is the gearbox under the battery tray almost thin pipe.

 

Any help would be greatly appreciated because when this car was running right its a lovely car to drive but this issue seems to be an issue that keeps raising its head.