Need MegaSquirt Help, I'm just getting into fine tuning. Options

[falconfp2001]

I spent about a week going back and forth to work and think that my VE table is about as good as I can get it. But now I need help with the EGO Control Settings.

I can't find anywhere where it has a recommended starting point for the
"WB Controller Settings" see pic.

I followed the recommended settings for tuning but now I'm trying to setup up for running and I can only find instructions for the upper part of this dialogue.

I'm using TunerStudio and MS2 Extra

Thanks

[rwilner]

I spent about a week going back and forth to work and think that my VE table is about as good as I can get it. But now I need help with the EGO Control Settings.

I can't find anywhere where it has a recommended starting point for the
"WB Controller Settings" see pic.

I followed the recommended settings for tuning but now I'm trying to setup up for running and I can only find instructions for the upper part of this dialogue.

I'm using TunerStudio and MS2 Extra

Thanks

Tuning a PID loop is non trivial, you can read about it here.

I would start with the defaults, and if you're getting pretty good tracking between your target AFR and the actual AFR, leave it be.

[falconfp2001]

I spent about a week going back and forth to work and think that my VE table is about as good as I can get it. But now I need help with the EGO Control Settings.

I can't find anywhere where it has a recommended starting point for the
"WB Controller Settings" see pic.

I followed the recommended settings for tuning but now I'm trying to setup up for running and I can only find instructions for the upper part of this dialogue.

I'm using TunerStudio and MS2 Extra

Thanks

Tuning a PID loop is non trivial, you can read about it here.

I would start with the defaults, and if you're getting pretty good tracking between your target AFR and the actual AFR, leave it be.

The defaults made my system oscillate big time. I followed the PID tuning instructions and it is now minimized and is pretty stable but there is still no real instructions on this part. I know the theory but it would be nice to have a starting point and not so much guess work.

[rwilner]

The defaults made my system oscillate big time. I followed the PID tuning instructions and it is now minimized and is pretty stable but there is still no real instructions on this part. I know the theory but it would be nice to have a starting point and not so much guess work.

In my experience, PID loop tuning constants are determined pretty much via experimentation. If you can characterize your system (frequency of oscillations, step response) you can use a more heuristic technique like Ziegler Nichols. Characterizing should be pretty easy to do using megalogviewer.

[jd74914]

The defaults made my system oscillate big time. I followed the PID tuning instructions and it is now minimized and is pretty stable but there is still no real instructions on this part. I know the theory but it would be nice to have a starting point and not so much guess work.

In my experience, PID loop tuning constants are determined pretty much via experimentation. If you can characterize your system (frequency of oscillations, step response) you can use a more heuristic technique like Ziegler Nichols. Characterizing should be pretty easy to do using megalogviewer.

(IMG:style_emoticons/default/agree.gif)

Ziegler Nichols gives good base-lines to start from, but beyond that may not be much help. You can also more analytically model your system (hello Simulink... (IMG:style_emoticons/default/rolleyes.gif) ), but in my experience, the most time-effective way to PID tune is by experimentation. It's really something that just takes a lot of experience to expedite.

[falconfp2001]

Thanks for the feed back. I tuned it somewhat and it no longer oscillates. I'm hoping this will work ok. My AFR seems to be stable but the only difference is idling for long periods while in inter city traffic. That is when it seems my AFR will dip and my idle speed will dip. It never goes below 750 but it seems to indicate that during on and off small acceleration I'm to rich. So, we will see.