Thread: Idle control - anti stall/idle recovery problem

Hi All,

I have been having a problem with my nismotronic causing a high idle after the engine nearly stalls, and not dropping back down if the car is moving. The idle will return to normal after I stop, but until then, the AAC duty is very high, and causing the engine to accelerate the car while in gear with the throttle closed. I have had a play around with the IDLE RECOVERY settings, but it doesnt seem to be the root cause. It seems as though the ecu doesnt exit IDLE ERROR and return to IDLE RECOVERY correctly if the car is moving. I also get a very high idle when turning the ignition off and back on again while the car is moving (I know this bad, but it used to be my only way to reset my MTX-L when it showed an error). I have uploaded a .TCD and a .TCL for everyone to have a look at. Things I focused on are TPS, AAC%, vehicle speed and RPM. At the start I'm just putting more load on the engine to intentionally bring it into the anti-stall range (I did stall it at first). It sometimes does this with just normal driving, as my clutch has a lot of bite and can drop engine RPM quickly if I get it slightly wrong. After this, the AAC duty goes to 88.5%, where it only needs to be at 50% to meet the target idle. This makes the engine push, and revs up when im changing gears, making it horrible to drive. The IDLE RECOVRY has a Min Speed of 8kph, but there doesnt seem to be a max speed for the IDLE ERROR? Or am I missing a setting somewhere?



I am also having this problem on a friend's car that is also running a nismotronic board. Any help will be greatly appreciated.

Thanks,
Kevin

http://www.se-r.net/engine/adjust_idle.html

Not sure if this will help. I had a similar issue and cleaning the iacv then doing this got things working.

Thanks, but this appears to be for stock ECU's. I'ts a bit different with the nismotronic board, plus I am able to see the IACV/AAC duty cycle and set it up manually

LOl, it's actually not much different, put the car into timing mode, set the timing and adjust the idle with the knob on the Iacv

It doesn't hurt to clean it either..

I dont see how this is funny? I've already cleaned it, and its only under this specific instance that it does this. The engine idles perfectly fine otherwise, with a reasonable AAC duty.

Has it been this way since you installed the NismotronicSA system, or was something changed and then it started doing this? What mods (if any) do you have? Have you tried another base TCD, or resetting your idle control parameters back to stock? Is your AFR reading correctly? It's running very rich ~9.0 at idle. These are only some observations/suggestions. I am not an experienced tuner.

Give this revision a shot!

When you load this calibration Hold Shift and press the Q key.

Thanks! I'll give it a go next time I'm out in my car.

Sorry, I didnt see this before. Its always been this way, but has been more noticeable with some other changes I have made. There arent any considerable mods, just the typical 2.5" exhaust, SR16VE cams, and a slightly ported intake. My AFR is around 14.5 ish at cold idle, and around 15.5 when hot. The AFR on the log is inaccurate, as my wideband was turned off at that stage due to a faulty sensor. I havent tried another base tune, and my idle control settings are how I want the valve to behave, but it just doesnt come off anti stall if the car is moving, and it holds the IACV at a high duty cycle until I stop.

I did try the JKTUNING's modified TCD, but I forgot to press shift+q, and I had the same results. I'll try it again shortly.

Thanks for your input so far guys.