Closed loop idle LSX

[LSXCutty]

Idle Closed loop.msl

I got the open loop idle to work pretty well and I may just stick to that.

I have been trying some different setting in the closed loop and nothing seems to fix the issue I am having. The idle verys when in park or neutral, but in gear it seems rock solid. and when puting the car into park the idle will go up somewhere around 1500. The log I'm attaching will show the car in park at first and then when I drop it into gear and then back into park. It seems to stay solid for a few seconds after the big jump after putting it back in park but then starts to go all over the place again.

[LSXCutty]

Ok going back and looking at the log a little bit more myself. I think the timing advancing is getting the idle to fluctuate. Do I sound like I may be on the right track?

[billr]

Yes, I think less spark advance at idle will help. It may not yield the very lowest idling MAP, but I think it will be more stable.

[LSXCutty]

I think the timing is advanced where I have it circled and that is messing with the idle when the car is in park or neutral. When its in gear the timing does not fluctuate and the idle is pretty consistent.

[LSXCutty]

Changed the timing and also turned off Idle advance. Did not change a thing. The stepper is moving pretty quick, So I also tried turning the sensitivity down without the desired result.

[muythaibxr]

Timing isn't the problem. You're fighting with unstable VE. Your VE is changing by ~5 points which is causing PW to change which is causing AFR to bounce between 13.9 and 14.5 which will cause RPM to bounce which will cause PID closed loop to chase the RPM which will just make the problem worse and cause an unrecoverable oscillation.

You *must* have VE and timing nailed down perfectly before trying closed loop idle speed control. You should probably also turn off closed loop EGO at idle until you get everything else working.

[LSXCutty]

So turn the ego up to 1300rpm or so and dial the fuel table in by hand where it idles in and out of gear to get a stable AFR?

[muythaibxr]

Yes.

[LSXCutty]

Thanks. I'll play around with it and see what I can get.