Rough idle and sputters at 4k

[thakingcb7]

Ok so I just bought this car last Wednesday and have been fixing little problems I find. But now I'm a little stumped as to what my next moves should be. As the title states... the car stutters at 4k and also has a rough idle. There no boost leak and I believe all sensors to be in working condition as there are no CEL's. Mods are: E316g, 3in turbo back exhaust, hard upper pipe, and RC 550's. I'm open to all suggestions.

 

[thakingcb7]

I hope so. I gotta start daily driving this thing soon because the kid I ride to work with got a DUI.

 

[thakingcb7]

So I'm digging around when I notice something that was tapped into the throttle body elbow so I traced it and discovered all this. Can anyone help me identify this?

 

[thakingcb7]

I'm thinking is a speed density setup but if so... what system is it for?

 

[thakingcb7]

Anybody got any information on this?