wiring block identification

I have a 97 sunfire 2.2 L engine.  Recently a wire has corroded and is causing MAJOR problems with the car - i.e. the engine won't run. (Starts but stops immediately).  Anyways I'm pretty sure this corroded wire is the problem...if not it still needs to be replaced.  I'm just not sure how to replace it because it corroded literally right at the end of the wire going into this block.  So my main question is does anyone know what this block is/ what its called, and how do you replace a wire right at the end.  Does it open up and I run a wire into it ? (Its the black wire thats corroded...its difficult to see in the zoomed in picture but I think u can get the idea.