On the passenger side manifold, it looks like there are 1 or 2 nipples on the manifold. I'm assuming this is for some type of pre-heating equipment that is no longer on my car? Are these actually holes going into the manifold? I'm asking because I hear a muffled fart noise that sounds a lot like an exhaust leak over there, and every time I drive the car, I smell like exhaust- even more so if I have the fresh air vents open. So, if these ARE open ports into the manifold, can I just have them welded closed while my exhaust guy checks over for other leaks? 68 Newport 383/727, for those who don't know already.