IAC position when driving along?
Posted: Sat May 02, 2015 11:12 pm
What happens to the IAC stepper when you are simply driving along? Does it close to minimum? Is there a setting in $12P for this parameter?
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IAC position when driving along?
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Re: IAC position when driving along?
Posted: Sat May 02, 2015 11:17 pm
usually it follows a throttle follower table.
Re: IAC position when driving along?
Posted: Sat May 02, 2015 11:27 pm
Something like "Throttle crack offset vs rpm"?
Re: IAC position when driving along?
Posted: Sun May 03, 2015 10:32 am
I would have thought that it would be IAC- Motor Park Position V's Load table that is then modified by the others such as IAC - Max Throttle Follower Steps Vs RPM and IAC - Max Throttle Follower Steps Vs Vehicle Speed
Ahh, OK, you're using 12p. The tables might be named a bit different.
Ahh, OK, you're using 12p. The tables might be named a bit different.
Re: IAC position when driving along?
Posted: Sun May 03, 2015 11:06 am
That looks like it sets the IAC steps for a snapped-closed throttle vs RPM:Circlotron wrote:Something like "Throttle crack offset vs rpm"?
- IAC_throttle_crack_vs_RPM.jpg (70.46 KiB) Viewed 3704 times
Re: IAC position when driving along?
Posted: Sun May 03, 2015 4:45 pm
The throttle crack table is for decel conditions as festy mentioned, during decel (or any operating mode) if the MAP is below "Idle MAP Threshold Vs Idle RPM" then the throttle crack multiplier is used. This is a trap if you have a high vacuum engine, it can be triggered at idle which will drop out of closed loop control and add some IAC steps. Once MAP exceeds the threshold the throttle crack offset is used. Like most things IAC, they are all offsets added to the base IAC steps (the learnt steps from closed loop idle control).
The IAC gets some steps added to the base when leaving closed loop idle speed and is what you see when cruising along, this is extended throttle crack. Its a few steps to help the idle return to normal next time you enter closed loop control, its so when coming to a stop or after a rev the RPM drops to just above normal target and can smoothly be controlled to target.
The IAC gets some steps added to the base when leaving closed loop idle speed and is what you see when cruising along, this is extended throttle crack. Its a few steps to help the idle return to normal next time you enter closed loop control, its so when coming to a stop or after a rev the RPM drops to just above normal target and can smoothly be controlled to target.