IAT resistor

Open loop is active while cold starting (as you mentioned) and then it goes to closed loop, depending mostly of the oxygen sensors and stay in that mode when cruising.

But, open loop is reactivated again as soon as the gas pedal is pushed past some point, let's say 20% for example.

It keeps in close loop as long as (1) engine is warmed up and (2) cruising at the same speed, without changes in acceleration for certain amount of time in seconds.

About IAT, you might try it if you want, but a complete loss of time and effort for me, as you won't get any result, at least noticeable.

If you want to try it by your self, we have a page with the info in our blog on how to correctly do it (in my signature, then search for IAT). At least, if you do it the right way, you won't be wondering if you did something wrong when you obtain no results.

Cheers,

Richard