Hello guys I am new member trying work on 3.5 engine and I learn alot from that engine wow anyway.... I take apart down for water leak behind rear timing cover I take of 3 bolt each side head but I noticed one bolt from cam gear (head cylinder bolt) there oil come out I scratched my head... I already block tester and Compressor test it all good over 120 each cylinder no lower

I check oil stick it has mix with water and I check on head take of valve cover both side had oil with mix water and freeze plug came out loose from behind rear cover timing

But the problem is where water come in motor ?? Is cuz oil pump no good or gasket .... Is oil cooler is not good