EQ Ratio Commanded with wideband in Lambda Issue

[minytrker]

LAMBDA LOG.hpl

How can I do AFR Error with this log? User defined math?

[schpenxel]

Your wideband is setup wrong. It's setup thinking it's AFR but actually reporting lambda.

You could do some crazy math parameter on your own to make it work or you can just fix the transform on the external input so that it's done correctly, then you can use "EQ Ratio error" for any future logs. AFR error only works when you are logging in units of AFR which is more trouble than it's worth. Use EQ ratio/lambda instead.

[minytrker]

Sorry I should have posted more details, I know how to set it up correctly, however its not my vehicle and I was sent this log to look at. This happens a couple times a year I'll get a log like this and figured there has to bea way to use the log with a user defined math but I cant figure it out.

[schpenxel]

Math parameter with the formula:

100 * ([40000] - [50118.238]) / [50118.238]

should work

[minytrker]

That seem to do the trick. Thank you! Now can you explain how you made that? I know how to convert between AFR, lambda, EQ ratio on a calculator for a single number but for the life of me I couldn't come up with that math formula.

[schpenxel]

Not a lot to explain. It's just the wideband reading minus commanded lambda / commanded lambda to figure out error. * 100 converts it to % and that's that.

The only weird part is that I'm technically using AEM's "AFR" parameter ID because that's what someone set it up as. It should have been setup as EQ ratio