94 Jimmy idle issue

I have a 94 Jimmy 4.3 VIN"W" with maybe an idle problem, when its in park it seems to idle ok but when I put in gear it kinda has a lope to it, was having hesitation problems but I believe that is fixed, I do have a code for the knock sensor, its not hooked up cause the wire is burnt but I got one form the JY to slice on the connector but on my knock sensor there is the bigger round piece that is missing where the connector holds onto I guess, is there something I can put on it to hold it on for now until I get to buy a new one? Would the knock sensor cause the lopey idle? And I put my head under the back in the tank area and I thought I heard like a sucking sound, like a vacum leak is that supposed to be there?

also forgot to say that when I try to rev it up in park seems like a miss, Im going to check plugs and all that in a bit, because sitting there idling it seems to have a small miss to it