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AFM.v reads zero

Posted: Mon Aug 12, 2019 8:51 pm
by NikkoPH
Hello All,

Did 3 datalogs today and AFM.v stays zero volts all the time.
Im using flashpro on a 2017 civic si. Software and firmware updated.

Trying to calibrate my AFM as my fuel trims are over 10%

Re: AFM.v reads zero

Posted: Tue Aug 13, 2019 7:19 am
by gtfrede07
Afm voltage is not log-gable on the SI due to the MAF design. AFM vs Strim is what I use in the scatter plot and line up the g/s numbers to the table cells.

Re: AFM.v reads zero

Posted: Tue Aug 13, 2019 9:04 am
by NikkoPH
Thank you for that information, i was hitting my head for no reason.
My graph shows +10% across the graph. Please correct me if i am wrong but i should adjust the g/s around -10%?

Re: AFM.v reads zero

Posted: Tue Aug 13, 2019 9:42 am
by gtfrede07
correct. then smooth out the surrounding cells on each end of your adjustment. I usually go half to 3/4 of the trimming percentage to prevent over shooting the adjustment. So instead of the full -10% I would do maybe -7 or -8%. Completely up to you.

Re: AFM.v reads zero

Posted: Tue Aug 13, 2019 10:12 am
by Spunkster
The 2017+ SI does not use voltage for the AFM, instead it uses frequency.

Re: AFM.v reads zero

Posted: Tue Aug 13, 2019 10:55 am
by NikkoPH
gtfrede07 wrote:
Tue Aug 13, 2019 9:42 am
correct. then smooth out the surrounding cells on each end of your adjustment. I usually go half to 3/4 of the trimming percentage to prevent over shooting the adjustment. So instead of the full -10% I would do maybe -7 or -8%. Completely up to you.
Got it, i was thinking of doing 3 increments, ill 7% and take it from there.
Spunkster wrote:
Tue Aug 13, 2019 10:12 am
The 2017+ SI does not use voltage for the AFM, instead it uses frequency.
Got it! Thank you for all your help!

Re: AFM.v reads zero

Posted: Wed Aug 14, 2019 8:38 pm
by NikkoPH
Datalog my commute today, around 91 ambient temp and really traffic. Here is what i found, my strim is around +18 across the board. It used to be +10 and i decreased by AFM by -10 yesterday prior to my commute today. Im surprised that s trim increase! What am i missing here? I don't wanna be running lean the whole day tomorrow.

Thank you!

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 4:49 am
by gtfrede07
miscommunication if its trimming positive you need to add to the afm number.

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 4:49 am
by gtfrede07
Jesus that plot is all over the place. I would highlight that whole table and increase +15% and re datalog.

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 5:03 am
by gtfrede07
As flat as the mean is I would almost suggest +20 and re datalog. Thats just a big swing in one go. Try the 15% and see if it still wants added to.

TO CLARIFY BECAUSE I CANT EDIT THE ABOVE POSTS IF S.TRIM IS A POSITIVE NUMBER YOU SHOULD INCREASE THE AFM NUMBER
IF ITS TRIMMING A NEGATIVE NUMBER YOU DECREASE THE AFM NUMBER.

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 6:12 am
by NikkoPH
gtfrede07 wrote:
Thu Aug 15, 2019 5:03 am
As flat as the mean is I would almost suggest +20 and re datalog. Thats just a big swing in one go. Try the 15% and see if it still wants added to.

TO CLARIFY BECAUSE I CANT EDIT THE ABOVE POSTS IF S.TRIM IS A POSITIVE NUMBER YOU SHOULD INCREASE THE AFM NUMBER
IF ITS TRIMMING A NEGATIVE NUMBER YOU DECREASE THE AFM NUMBER.
That is where i got confused, i have reloaded the +6 calibration and adjusted +10.

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 10:39 am
by NikkoPH
gtfrede07 wrote:
Thu Aug 15, 2019 4:49 am
miscommunication if its trimming positive you need to add to the afm number.
To clarify, if the STRIM is within negative values i should adjust by putting a (-) negative value towards zero and if its within positive value i should adjust by putting a (+) positive value towards zero. Please correct me if i am wrong

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 11:25 am
by Spunkster
negative trim means it is removing fuel because it is too rich and you need to lean it out.

positive trim means it is adding fuel because it is to lean and you need to richen it up.

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 11:48 am
by NikkoPH
Spunkster wrote:
Thu Aug 15, 2019 11:25 am
negative trim means it is removing fuel because it is too rich and you need to lean it out.

positive trim means it is adding fuel because it is to lean and you need to richen it up.
Hi spunkster, i got that concept. Base on the graph i attached i need to richen up. My question now is should i be adjusting the AFM or g/s in the calibration?

Thank you!

Re: AFM.v reads zero

Posted: Thu Aug 15, 2019 4:48 pm
by Spunkster
It is the same idea as what is in the help file: https://www.hondata.com/help/flashpro/t ... m_flow.htm