I have been trying to adjust the air screw on my 2001 AT on either side of the 2 3/8 turns out, and it seems to make little difference. So that I can at least have an idea of what I am doing, could someone tell me which way it works? Does unscrewing it make the mixture richer or leaner? I have seen a post on this, but the answers contradict each other. Seems like a basic question, but the manual doesn't say anything about it, and it would be good to have the definitive answer on this.