98 Z71 Power Steering Pump
 

I have replaced the power steering pump on my 98 Z71 with a 5.7L twice and it still does not handle correctly.
When I get the new pump it does not have the electrical plug in on the back at the high pressure line connection so I have to take the old assembly off and reuse it. Does anyone know what the plug is for and do I need it?
I am wondering if there is something wrong with the relay or what ever the part is that I plug into as that is the only thing that is not new and I cant find anything on it to replace it.