Re: LS1 cylinder head
That can be one of the hardest to get to. is it possible that it never got tight enough and walked out? in that case just tighten it up. If it actually broke you might have to have a shop do it unless you have the right tools to get in there. I know from just changing the plugs it was very difficult to tight both back ones all the way down. whoever changed them before might of said "good enough" and not torqued it.
98 Camaro Z28/SS Clone, SLP lid, Throttle body spacer, Electric Exhaust cutout, Front strut bar, K&N Air filter, poly sway bar bushings, Full synthetic oil, Auto