Ok. I don't know if I have EVER had a problem with ANY 12 valve injector lines leaking. The ISB lines will leak habitually there ( at the injector connector) It's quite a battle.
I'd loosen up all your hold downs and then loosen up all the lines at the nozzels. Then snug down the nut and tighten all the hold downs again.
You don't have to use a pipe on the end of the wrench either. Snug is good. If you have a torque wrench with the adapter and proper wrech to attach it to, knock your self out. I have no idea what the specs are.
GL