Ckranking slow stalling surging

We have a buick park ave 95 3800 seires 2 code k it died when I was HELP checking it water wascoming out throttleboby while pressuering rad while ckranking so ichanged upper intake gasket tryed to start but had same prob and while ckranking it was ckranking slowly itermittly found hole in upper intake changed it an it started up but sense then ititermittlt stalls ckanks slow serges with volt meter jumping up an down no check engine light so I changed starter an cleaned IAC ckanking got alittle better but still there had charging/starting sys check by pro armature shop they found no prob I tried test battery still have problems could cylinders be fireing againsed each over forgive spelling HELP