I'm curious what these do:

Max cold RPM in kickdown mode @ 5E1
Max RPM hot park/nuetral @ 5E2
Max throttle follower bias @ 5F2
Temp for cold RPM limiting @ 5F3

I have a big file going on what all the data locations do and a brief explanation of how they affect / interact with things. Thanks for any input.

 

V8,

I believe there's an artcle by RBob describing the IAC functions you are looking at. I spent the better part of last summer just playing with that stuff. I had put on larger TB's and wanted to limit the amount of IAC opening so more air would be forced through the now larger venturis. It really makes a difference on the idle quality and the throttle response.

0x5F2 is Max Throttle follower in steps. The IACs will open in conjunction with the throttle opening. This address puts a limit on how many total steps the IACs can move in following the throttle opening. In stock bins you'll find 145steps typically. Mine is limited to 65 so that more of the air is sucked through the venturis and not bled past them through the IAC valve. The original intent of this mod was to increase total air flow by using the IAC passages as well, assuming you had stock TB's. But with larger TB's that isn't necessary and in fact you'd like to maximize total air flow through TB's in order to maintain higher A/F mixture velocity. Modifying this helps to minimize or eliminate bog when using larger TB's.

0x5F3 is the temp that allows kickdown and allows ECM to utilize values in 5E1, 5E2, 5E3.

 

Cool. Thanks Dom.