the guy writting the SCT programs for me said he can force it to stay in open loop. I was asking about possible future upgrades, to include a 5.9L swap with a cam ground on a 106 LSA. he said "no problem, we can do it, but I'd have to disable closed loop because all the overlap will make the computer think it's running rich when it isnt."

I'm not sure how much he can manipulate the stock computer though, if it is going to maintain the factory set calibrations on AFRs etc.

right now I've got to figure out what's making the computer pull the IAC wide open when I let off the gas--something in the timing and vacuum signals must be making the engine think it's about to stall out, and it opens up the IAC so wide, it holds a 3000 rpm idle while the truck is still rolling, but once I come to a full stop, the idle drops back down to 750.

I put it into neutral or step on the clutch, and the RPMs drop from 2500 to about 2,000 then the IAC slowly opens fully and it gradually climbs back up to 3000 rpm on the "idle"