does iac track rpm or massflow
does iac track rpm or massflow Does the IAC adjust to keep a constant idle speed or a constant idle airflow? For example if i were to change the idle air tables to like 20 g/s would the engine rev up?
FormerVendor
Joined: Jan 2003
Posts: 525
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From: Melbourne, Australia
Originally Posted by P Mack
Does the IAC adjust to keep a constant idle speed or a constant idle airflow? For example if i were to change the idle air tables to like 20 g/s would the engine rev up?
if you set it up to 20, the dynamic adjustment would pull it back to the idle RPM. The idle control for the IAC has the equivalent of a fast learn and slow learn (kinda like STFT's and LTFT's) and it remembers the last position the IAC was in under the various combos of PN/Gear/ACon/off (again kinda like the fuel cells).
In my own private "let me break stuff" version of our s/w i have full visibility of all the airflow components that make up the final idle airflow that drives the IAC. It takes a little time to get all this into the scanner since very few of these parameters are available via GM PID methods and it becomes custom per operating system. That reminds me i think i said i would post a detailed description of the Idle airflow a while ago...
In future look forward to "I got my idle trims at -0.8, what next?"
Hope that helps.
Originally Posted by gameover
In future look forward to "I got my idle trims at -0.8, what next?"
Yeah that helps a lot, thanks. So by the components that make up the final idle airflow do you mean like throttle cracker, throtte follower, and "idle trims"? If you could post kind of an explanation of how those work together that'd be really helpful even without the ability to log them.
TECH Addict
Joined: Jul 2002
Posts: 2,261
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Originally Posted by gameover
In my own private "let me break stuff" version of our s/w i have full visibility of all the airflow components that make up the final idle airflow that drives the IAC. It takes a little time to get all this into the scanner since very few of these parameters are available via GM PID methods and it becomes custom per operating system. That reminds me i think i said i would post a detailed description of the Idle airflow a while ago...
Hope that helps.
Hope that helps.
Gameover,
Yes, it helps.
Can you post the relationships of the Throttle Followers(Decay Tables), Idle Air and IAC Park - for ETC ????. Are the Airflows identified by the Throttle Follower and Throttle Cracker tables added to the Idle Air value?? What are all of the values that make up "Final Idle Airflow"??
joel FormerVendor
Joined: Jan 2003
Posts: 525
Likes: 0
From: Melbourne, Australia
Originally Posted by Bink
Gameover,
Yes, it helps.
Can you post the relationships of the Throttle Followers(Decay Tables), Idle Air and IAC Park - for ETC ????. Are the Airflows identified by the Throttle Follower and Throttle Cracker tables added to the Idle Air value?? What are all of the values that make up "Final Idle Airflow"??
joel
Yes, it helps.
Can you post the relationships of the Throttle Followers(Decay Tables), Idle Air and IAC Park - for ETC ????. Are the Airflows identified by the Throttle Follower and Throttle Cracker tables added to the Idle Air value?? What are all of the values that make up "Final Idle Airflow"??
joel
