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My son has a 98 VS V6 Getrag Manual ute, & for as long as he's owned it, it's had this odd problem where the idle speed stays at around 1000 rpm if you push the clutch pedal in when rolling, even if only rolling along at 5k's/hr, then returns to the usual 780/800 rpm the second the car stops rolling..

Iv'e done a search here & google, most findings get hits about setting target idle speed in tunerpro, though I can't imagine why a STD unmodified tune would do that, check light has never come on to indicate faults at any time..

Any input as to why it does it would be greatly appreciated..

Thanks..!

if its rolling it knows its moving and it does not try to idle. when the speed is under the max speed for idle mode idle mode turns on then it'll let the revs drop to the idle speed determined by (i think) temperature and voltage. You could load the matching XDF to see the parameters.

Ok, I figured it was just an odd scenario, I didn't remember his previous 95 model doing that, thought it may have been a problem.

You should be able to adjust rolling iac steps

delcowizzid wrote:You should be able to adjust rolling iac steps

Did a search in tunerpro for either "rolling iac steps" or just "iac steps", couldn't really see anything that indicated it might influence what I'm seeing..
After removing the TB & cleaning it & the idle motor, resetting the computer then going for a drive getting some temp into it, I did a few more tests.
I found that if I pushed the clutch pedal in when rolling at speeds above roughly 25ks, it dropped to normal idle speed, though pushing the clutch pedal in when rolling at less than 25ks, the revs picked up to 1400+ rpm, & stayed there until 100% stopped, I even sat stationary at the top of a long hill, let the car roll & pick up speed, without touching the throttle, the revs picked up to 14/1450 mark, then when we hit the 25k mark whilst rolling, the revs dropped back to proper idle speed..

in 12P there is some stuff called idle drive (ie driving on idle alone) so perhaps there maybe something called that on yours as well?

vlad01 wrote:in 12P there is some stuff called idle drive (ie driving on idle alone) so perhaps there maybe something called that on yours as well?

Yeah I saw that entry when doing a search just for the word idle in tunerpro..
I've pretty much fiddled with all & any option that was associating any speed setting with idle, & then some..
What makes it worse, is it only raised the idle to around 1250 rpm on the STD unmodified tune, then when I gave it a few degrees timing it's another 200rpm.
I'll keep fiddling, time permitting, the amount it flairs can't be normal..
Seems this has happened to others before & the reason was never found, I did find a post on the forum here from some time ago.

Is this anything to do with the IAC throttle follower settings? What would be the IAC position when the high idle issue is present? Or how far does the IAC have to travel to get back to its usual idle position? Does it have a long way to travel or is it pretty close? Would increasing the IAC steps for idle so it was closer to where it is at 5km/hr make it better or worse? If the 2 are pretty close it wouldn’t make any difference I guess, but it would cost nothing to try it.

I've played with the IAC steps to the point that all options were tried.
Out of desperation, I flashed the last T5 manual tune to the memcal & went for a drive, to my surprise, it not only worked, but no high idle problem below 25k's..

What I did find was this setting below which may have something to do with why my altering settings has no effect.. Also, I've found spelling mistakes & a hex address pointer that was wrong in the 1.04_Getrag.xdf, should I upload the corrected one here, or just point out the errors.

That's very odd, normally that is set just slightly higher than thermostat temp.

I'm surprised the T5 tune worked considering it's looking for a different speed sensor input.