lq4 99 4 Runner- erratic idle and/or stall sometimes when moving slow or stopping

[LQ4 V8 99 4runner]

Hi all, I'm new here and I have a 99 4runner modded with an lq4, 4l80E, and a street cam. This setup has been tuned by someone with what I consider a lot of tuning experience. The problem is every so often when moving slowly or coming to a stop (both with air on or off) the idle will start going up and down a lot and sometimes stalls. The tuner has not been able to fix this issue so I bought the programmer and I'm hoping to find some help here on this great forum. We have logged all the data when this problem occurs and we see that the IAC basically stops moving or moves very little while the idle cycles up and down from 900RPM to less than 500RPM. On one log this lasted 5 seconds and also during this time the Spark advance freezes and does not move. When this condition occurs it will either stall or after some seconds corrects itself and the advance and IAC starts moving again. Does anyone know what could cause this? Other than this it runs good and always idles ok when not moving. Your help would be greatly appreciated!!!

[LQ4 V8 99 4runner]

Help Please! Can anyone help me with this issue as my tuner can't find the solution.

[5FDP]

Gotta post the tune and logs of it happening.

Can't see what you see without it.

[LQ4 V8 99 4runner]

Gotta post the tune and logs of it happening.

Can't see what you see without it.

Ok Thanks a lot! I will post those files this evening.

[LQ4 V8 99 4runner]

Ok Thanks a lot! I will post those files this evening.

Attached are my tune file and my log file showing the problem starting at 9:01:17.700 and going until 9:01:24.759.
Thanks!!!

my 4 runner tune rev 2.hpt

4runner open loop 5 idle up and down.hpl

By the way the log was done before I changed my idle from 850 to 900 which is now in the tune file.

[5FDP]

Does this issue happen in just open loop or when the calibration is set to closed loop?

Only looking at it real quick here, have you tried less timing at idle and lowering the under/over speed corrections a little so it does less. Like maybe try 18-20 degrees of requested timing instead of 24 degrees.

Somewhere on this forum is also a RAF (running airflow) guide that you can try to follow to see if that will help you any.

[LQ4 V8 99 4runner]

Does this issue happen in just open loop or when the calibration is set to closed loop?

Only looking at it real quick here, have you tried less timing at idle and lowering the under/over speed corrections a little so it does less. Like maybe try 18-20 degrees of requested timing instead of 24 degrees.

Somewhere on this forum is also a RAF (running airflow) guide that you can try to follow to see if that will help you any.

Thanks for you reply!
Yes we had similar trouble with it in closed loop, but it has been tuned in open loop and it runs better that way so we left it like that.

I don't know if the tuner tried what you mentioned, but I haven't as I'm new to this stuff.

Do you have any idea why the the Spark advance freezes and the IAC does not move only during the trouble period. My tuner thought that was of importance but not sure what to do about it.
Also It only happens when moving slowly (stopping or switching from Rev to Drive or visa versa and moving a little), if I stop it seems to correct itself.

Thanks again for your help with this!!!