injector wire fasteners

I pulled valve cover and on my ved12 and bingo,wire fastener was loose on one post,code was electrical fault on #5 injector,now my question is this threaded nut or a ribbed post? post seems sturdy.could threads be stripped? how should I go About re-securing?thanks in advance.

 

after closer inspection I noticed half the post sheered or cracked off in vertical angle allowing threaded nut to jiggle on the post, the hole in the nut looked goose egged I ran a solid piece of copper wire between nut and post , when I turned the nut it tightened down the wire , not the way I like to fix things , Volvo said it would be a week before they could look at it , probably lucky for me, driving with engine missing and throwing codes was stressing me out , be careful not to strain your back when pulling valve cover it's awkward , I secured wire on nut so it wont fall off into oil port or valve rockers, ask several repairmen if they'd seen this , no one had no clue was broke post, I hear these wires carry enough current to kill a man, so make sure no current when touching wires, hope this may help someone else,