After 3 days in the OR, my '84 XJ 2.5 w/YFA & 4spd starts, idles, runs, and SMELLS better. Having searched in vain for a clear, concise, one stop tech article, I've written my own. This is for everyone with an AMC 2.5 4 cyl. w/ a Carter YFA carb and the full PulseAir (P/A) emissions...