On my d15b2 (dual point) the throttle sticks whenever i give gas. However ive narrowed the problem down to the plate where the throttle cable attaches to. The problem is the plate doesnt return back to where it should be (zero throttle)instead it sticks as if youre giving gas. Ive already tried loosing/thighting the screw on the plate and cleaning the spring. And usually idle surge occurs from this problem

Any solutions?

 

Remove entire throttle body, and clean it inside and out with a can of carburetor cleaner and a toothbrush.