Weird idle issue

[joncurry94]

So a friend of mine was helping me clean the throttle body and he accidentally broke a really cracked hose, so he tried to replace it. Since then I have been having this weird issue where I am idling at 1,100 RPM's until the car starts to get hotter. 

Attached is the image and you can see the hose that was replaced with non oem parts, kind of rigged up. What is the black plastic cover and what are the three hoses that go into it? I am trying to replace all three because they are all sort of damaged just from the heat over time.