[JimNNN]

I find that my idle mixture screw adjustment requirements can change with the weather. If I really wanted to keep my car idling perfectly, I would probably need to fiddle with it just a little every time I drove it. For example, yesterday it idled perfectly, and I did nothing to it. A few days earlier, though, the idle was OK, but not as smooth as yesterday. On really hot humid days, it never actually idles perfectly smooth. I have the original carb.