to do it properly

run engine up to temp
unplugg the iscv (leave engine running) (iscv is on top the throttle body grey plug)
adjust idle on throttle body screw to 900rpm
re connect iscv, and idle should stay stable. (you need to do the above before the cooling fans come on!)

then 5 turns on the screw, this takes it back past zero, then 2.5 turns out.
Remember,its a potentiometer, not a normal screw, so it only adjusts a certain amount, no more or no less, even if you turn it 100 times, turning it back 5 times will still take it to zero.

what chip are you running and what does the CO% have to be at idle according to your chip?