idle relearn, expected IAC steps?

scott0999 · December 04, 2009, 10:38:15 PM

I heard theres a setting "INIT FOR ISMNMPKA WHEN KEEP ALIVE RAM FAIL"

for adjusting IAC steps so you shouldnt have to do idle relearn (as much) anyway

my question is, when I bring this up it shows in TPS %. is this correct? I would think it should be in IAC steps?

scott0999 · December 14, 2009, 01:02:15 PM

heres what I've found. looks like the XDF settings were wrong for this. I was reading a tuning guide for $DF when I first came across this setting. it shows in IAC steps for that code mask.

so I tried putting the $DF XDF settings into $8F and came up with this:

so basically if thats right it means the ECM is expecting 12 IAC steps for idle. anything more/less the ECM would need to relearn and store in its memory

since my car is 5spd (along with other mods), my IAC steps are much higher.

is there anyone on here with a stock TGP that could verify their IAC steps at idle? that would be a great help in determining if my XDF fix is right

once winter is over I will be able to try this out. I'm sick of idle relearn taking forever when I disconnect the battery. I'm pretty sure this will fix it

flybynite · December 14, 2009, 06:52:57 PM

What problem are you trying to cure?

scott0999 · December 14, 2009, 06:59:30 PM

Quote from: flybynite on December 14, 2009, 06:52:57 PM
What problem are you trying to cure?

whenever I disconnect the battery it takes way too long to relearn the idle. it stalls for days then its fine

TGed · December 14, 2009, 07:20:46 PM

Mine randomly would stall too, and mine is an automatic. I never could figure it out and neither could the second party tuner. Ran great and afr/tune was great!

scott0999 · December 14, 2009, 07:22:03 PM

Quote from: TGed on December 14, 2009, 07:20:46 PM
Mine randomly would stall too, and mine is an automatic. I never could figure it out and neither could the second party tuner. Ran great and afr/tune was great!

what size injectors?

flybynite · December 14, 2009, 07:35:21 PM

Quote from: scott0999 on December 14, 2009, 06:59:30 PM
whenever I disconnect the battery it takes way too long to relearn the idle. it stalls for days then its fine

Have you tried raising the idle set screw? This will allow the iac to have minimal steps and it is less likely to fluctuate.. Just a guess tho...

TGed · December 14, 2009, 07:41:02 PM

Quote from: scott0999 on December 14, 2009, 07:22:03 PM
what size injectors?

It happened with 28's, and 36's. since that is all that I tried so far. The motor is long gone and a new build is under the knife for next year. Going with 8f again and 42's .... :eek:

My idle wouldn't fluctuate, it would idle perfect and just randomly stall when coming to a stop or while costing at low speeds (20 or under) .

scott0999 · December 14, 2009, 07:47:16 PM

Quote from: flybynite on December 14, 2009, 07:35:21 PM
Have you tried raising the idle set screw? This will allow the iac to have minimal steps and it is less likely to fluctuate.. Just a guess tho...

thats what I did when I had megasquirt on the car and it seemed to work. well I kinda had to do it that way since there was no idle control... but I have a 65mm TB and the set screw doesnt stay locked so that wont fix it. It seems the problem is in the tune since it relearns the idle eventually. so I would rather fix it that way

scott0999 · December 14, 2009, 07:50:57 PM

Quote from: TGed on December 14, 2009, 07:41:02 PM
It happened with 28's, and 36's. since that is all that I tried so far. The motor is long gone and a new build is under the knife for next year. Going with 8f again and 42's .... :eek:

My idle wouldn't fluctuate, it would idle perfect and just randomly stall when coming to a stop or while costing at low speeds (20 or under) .

last car I tried tuning w/ 42s on 8F was a nightmare. but the car had some issues so im not blaming 8F 100%

let me know how your tune goes. I might attempt it again when that car is in better shape. it had some vac leak issues and maybe even exhaust leaks. my car took forever to get a good idle with 39#s and thats with it in good shape lol

TGed · December 14, 2009, 08:00:00 PM

It will be a while unless I find someone more open minded with code 59 and willing at the same price.

flybynite · December 15, 2009, 05:55:55 AM

Have you tried messing with the IAC vs MPH table. I have tuned up to 42lb injectors with all sorts of issues. In the end everything worked out, it just took some time...

scott0999 · December 15, 2009, 09:15:34 AM

Quote from: flybynite on December 15, 2009, 05:55:55 AM
Have you tried messing with the IAC vs MPH table. I have tuned up to 42lb injectors with all sorts of issues. In the end everything worked out, it just took some time...

havent tried that, I dont see it in my XDF? could you send yours

flybynite · December 16, 2009, 09:22:49 AM

The xdf on 60 has it. IAC Throttle Follower Decay Rate VS MPH (not in park or neutral).

scott0999 · December 16, 2009, 10:15:23 AM

Quote from: flybynite on December 16, 2009, 09:22:49 AM
The xdf on 60 has it. IAC Throttle Follower Decay Rate VS MPH (not in park or neutral).

k, found it. mine is showing 16 steps at 0mph. thats too low lol. thanks alot, I'll report the results when the car isnt frozen :)

edit: wait its showing msec is that right??