I changed from the stock intake manifold & TB to a F A S T LSXrt manifold and a 102 mm TB, I also changed Cams, from 226/226 .585/.585 112 LSA to 226/230 .598/.600 113+2 LSA. I also had the heads shaved .050.The engine is a 5.3 with stock bottom end I'm having trouble with the idle and I've never tuned for idling before. What do I need to scan to find out where my problem is. I'm not sure what PID's to set up in the primary table. Please keep it simple. The Idle in gear is not bad but in neutral it starts up at about 2000 then slows down for a little while, around 900 then it speeds back up then slows down then stops. If I touch the accelerator it speeds way up.