Commanded Lambda and lambda error %

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03-16-2016
jimbos'ss

4 Attachment(s)

Commanded Lambda and lambda error %

I was out tuning with what I though was the correct setup for Lambda based on the preconfigured maths. I kept overshooting my target by a good percentage, kept wanting me to lean it out more and more and by a big percentage. So I started messing with the units for commanded eq ratio and realized on that particular pid Lambda is actually phi and vice versa. So in the end I had to create a custom math that utilized that pid as phi instead of lambda. see pics below.
http://www.hptuners.com/forum/attach...id=57425&stc=1
http://www.hptuners.com/forum/attach...id=57426&stc=1
http://www.hptuners.com/forum/attach...id=57427&stc=1
http://www.hptuners.com/forum/attach...id=57428&stc=1

as you can see after two flashes it had pushed me incredibly lean and I didn't even know it. I went and validated my new custom math and it works correctly now. Tomorrow I'll dial my map back in to where it needs to be. Thankfully I didn't pop a piston just in time for TX2k.

Logging with V3.0.55
vehicle being scanned is Gen3 2001 z06 2bar OS.
03-18-2016
schpenxel

Maybe I'm missing something. Why isn't EQ ratio commanded showing up in the chart?
03-18-2016
mowton

You need to set up a filter which will limit your data to valid scenarios only (no idle, decel etc). Use the filter below. You will need to add Fuel trim Cell parameter to your Channel and Chart. Add this filter to your VE error Graph. It shows only error data when you are in valid FTC, TPS >30% snd filters throttle transients and ECT greater than 176. You may need to change the TPS/ETC parameter based on what you are logging.

([6310]=0 or [6310]<16) AND ([17.156] > 30) AND ([17.156.avg(500)] > 30) AND ([17.156.avg(-500)] > 30) AND [5.242]>176

Ed M
03-18-2016
jimbos'ss

Sometimes when I open a log it won't read the data for a parameter. Usually I just close the scanner and reopen to fix it.
03-18-2016
jimbos'ss

Quote:

Originally Posted by mowton

You need to set up a filter which will limit your data to valid scenarios only (no idle, decel etc). Use the filter below. You will need to add Fuel trim Cell parameter to your Channel and Chart. Add this filter to your VE error Graph. It shows only error data when you are in valid FTC, TPS >30% snd filters throttle transients and ECT greater than 176. You may need to change the TPS/ETC parameter based on what you are logging.

([6310]=0 or [6310]<16) AND ([17.156] > 30) AND ([17.156.avg(500)] > 30) AND ([17.156.avg(-500)] > 30) AND [5.242]>176

Ed M

I haven't got around to setting up filters yet even though it would save me a bunch of time. This is more as an informative thread to show that the unit definitions are inverted on this pid.
03-18-2016
mowton

Quote:

Originally Posted by jimbos'ss

I haven't got around to setting up filters yet even though it would save me a bunch of time. This is more as an informative thread to show that the unit definitions are inverted on this pid.

OK I see....so may be stating the obviuos again but .....what parameter is in the Channel table that you are using to develop the commanded lambda value in Math? In the Chart, insert the parameter Commanded Lambda from the Math element you developed. Then the Lambda Error Math expression will have to contain that same equation written out for the commanded Lambda (twice) as you can't reference a Math .xml in another math equation.

Hope this helps...if not Please post your Channel, Math and Layout with a log so we can check it.

Ed M
03-18-2016
jimbos'ss

3 Attachment(s)

Attachment 57457 Attachment 57458 Attachment 57459

Attached is my current setup with updated graph and custom math. I still owe bill some logs on this,just haven't gotten a chance to send them.
03-18-2016
mowton

Quote:

Originally Posted by jimbos'ss

Attachment 57457 Attachment 57458 Attachment 57459

Attached is my current setup with updated graph and custom math. I still owe bill some logs on this,just haven't gotten a chance to send them.

Still need Channel (what commanded EQ is being logged) and a log to get it to work. Again, if I understand the issue, the Commanded EQ you are using is PHI so you need to generate generate a commanded lambda (math.xml) which would be 1/Commanded Phi....Then that equation has to be used in your Lambda Error math equation replacing the ... [50118.239]) / [50118.239] with ... (1/[50118.239]) / (1/[50118.239]). This assumes your Channel parameter is [50118.239])

Ed M
03-20-2016
jimbos'ss

My commanded EQ channel is 50118.239 that's for phi which actually reads as Lambda. 50118.238 is supposed to be Lambda but reads as phi.
03-21-2016
schpenxel

Let [email protected] know what is going on.

There were some weird issues with the way GM reported "EQ Ratio" back when V3 was in beta. On some ECM's the EQ Ratio PID actually reported commanded lambda, and on some ECM's it reports EQ ratio like it's supposed to.

It sounds like this ECM/OS is inverted from what it was expected to be.
05-03-2016
RawRacing

Was this fixed? I just noticed that EQ ratio isn't reading correctly on a C5Z I was tuning last night. At 14.7 it was 1.0 but when going into WOT and commanding 12.5 the EQ ration would read 1.16. The scanner would tell me I was off target by 30-40% at times but I ignored it as my AFX was reading .8-.85. So is the scanner reading in Phi the issue?
05-03-2016
schpenxel

If you're on the latest version (3.0.97) and it's still doing it then it's not fixed for that vehicle.. let support know. It's showing "EQ Ratio" in GM's terms when it really needs to be inverted and showing commanded lambda for the formulas to work. You could create your own math parameter for AFR/EQ error real quick to get around it if you need to get finished with the car.
05-03-2016
RawRacing

Quote:

Originally Posted by schpenxel

If you're on the latest version (3.0.97) and it's still doing it then it's not fixed for that vehicle.. let support know. It's showing "EQ Ratio" in GM's terms when it really needs to be inverted and showing commanded lambda for the formulas to work. You could create your own math parameter for AFR/EQ error real quick to get around it if you need to get finished with the car.

I'm using 3.0.79 so I'll download the latest version and check. I just used my wideband and logged it vs the MAF to make changes. I'm creating the custom EQ ratio as laid out above by Jimbo, so I'll check today if it works properly. I noticed something similar but not as bad with a 2002 Silverado I tuned.
05-08-2016
jimbos'ss

I unfortunately left my laptop charger in Houston and had to pull my motor out so I never got the data off to support. If it's not fixed, see above for the workaround. Mine is also a c5z.
05-15-2016
RawRacing

Quote:

Originally Posted by jimbos'ss

I unfortunately left my laptop charger in Houston and had to pull my motor out so I never got the data off to support. If it's not fixed, see above for the workaround. Mine is also a c5z.

I downloaded the latest 3.0 and it hasn't been fixed, I just ran into the same problem with a 2002 Silverado along with the C5Z. Thank you for posting your work around as it saved me. I built the custom math parameter like you explained and it worked great!
05-24-2016
2000_SS

Same here, on a 01 WS6. I need to send that in to support I suppose. Good thread, thanks for the help.
06-02-2016
Z06-Hammer

Had the same issue today on a 2002 Truck running the latest beta.
06-02-2016
schpenxel

Post logs/send to support so they can fix it. GM is all over the place on whether they actually report out what they should. Some models report EQ ratio, some report lambda..