Idle control issues LSx 5.3L Turbo

[kingtal0n]

Having some trouble getting the idle sorted out with this brand new 4-wire Idle control motor.

First, attached here is the tune file, as well as a couple of datalogs that I made both wot passes, and idle/starting situations.
Next post, I will share specific pictures and details of the issue(s).

[kingtal0n]

One of the strange issues is this. Its really two issues I think they are connected.

1. Out of the blue, seem at random, the Target idle rpm will skyrocket to some number, usually 1600-1800rpm. the rpm will follow and sometimes it will surge like this for a while then suddenly stop. I don't have any target idle rpm set that high anywhere; I am not sure where it is getting that.

2. When I touch the throttle even just a tiny bit, the RPM will also go really high for some period. If you check my tune file you see I made several corrections in attempt to remedy this, such as slowing the idle valve and removing the dash pot (set to 0). Nothing seems to help.

Also notice that, even though the idle stepper seems to open ALOT, the RPM still continues to fall. I wonder if it is working correctly (its brand new) might be bad?

3. Also, when viewing log files, the little map on the right doesnt follow the RPM. In other words, the little box just sits on 7000rpm no matter what the true rpm of the engine is. So I cant play back my log files appropriately to see where on the map it was following.

[kingtal0n]

The next picture is something odd I caught. It might be related to the trigger wheel or noise. The rpm just "goes nuts" 54,599 rpm etc... and the engine died

[kingtal0n]

a picture of the idle control unit

[kjones6039]

First, attached here is the tune file, as well as a couple of datalogs that I made both wot passes, and idle/starting situations.
Next post, I will share specific pictures and details of the issue(s).

The first thing that jumped out at me was, 124.8% TPS............

You'll need to calibrate that.

Ken

[kingtal0n]

I keep re-calibrating the TPS and it keeps moving on its own. I am aware of the problem but nothing I can do about that at the moment. The datalog shows than TPS is at 0% when the idle target spikes so it has nothing to do with the TPS.

[jlawson05]

Are you sure you have the stepper motor set up right? My lsx 4 wire has the following settings. I attached the following pictures of my settings. I set it to closed and moving only. Plus I use the "Basic" PID closed loop control function. My ls has a wild cam and MS3 controls it GOOD. I attached the msq for you to look at.

[kjones6039]

I keep re-calibrating the TPS and it keeps moving on its own. I am aware of the problem but nothing I can do about that at the moment. The datalog shows than TPS is at 0% when the idle target spikes so it has nothing to do with the TPS.

I never intended to imply that TPS calibration was the cause of your issue!

I shall retire to my corner and keep my mouth shut.

Ken

[kingtal0n]

Hey thanks guys, that was really nice of you, I appreciate all comments.

No need to worry, please feel free to say anything

[dll67]

Did you solve any of your problems .. Was it something unusual or was it just a floating sensor input?

[zracer]

Spiking RPM can't help.

IAC maybe. That looks like an ebay throttle body, I had trouble getting my ebay IAC to work with setting others used for stock IAC valve. I'm running open loop with low RPM timing bump to get idle. Here are the setting I used to get it working, hold current was the key. 4.8 ls turbo setup.