NGK AFX Stoich Value

[dmaxjm]

I was just wondering after looking at the NGK AFX AFR PID within the scan tool, does it need to be corrected for stoich value? My LS1 Vette has a stoich value of 14.63 and the wideband O2 has a stoich value of 14.57. I know the difference in reality is 0.4% but would that make a big enough difference? Should the following PID information for the NGK AFX be something like...

AFR = {EXT.AD1}*1.4+9 *(14.63/14.57)

Here is the default PID...


Wide Band AFR 1 - NGK AFX {CALC.AFR_NGK1}

Expression:
AFR = {EXT.AD1}*1.4+9
is VALID


Also, if I do need this change how can I edit the PID or do I have to recreate another PID for the NGK AFX AFR? Thank You!

[joecar]

You would do this:

1. set your B3601 to the stoich AFR of the fuel you're running (E10 is 14.2, E85 is 9.7).

2. for tuning, instead of calculating AFR, calculate lambda, as follows: AFR = ({EXT.AD1}*1.4+9)/14.57

3. if you really must see AFR, then consider if you want to see actual AFR (based on stoich of fuel being run) or gasoline AFR (based on gasoline stoich 14.6)... and multiply the lambda expression by this stoich value, e.g. AFR = ({EXT.AD1}*1.4+9)/14.57*14.6

Of course, you would do the calculations in the calc_pids.txt file.

:)

[joecar]

Copy the attached calc_pids.txt file to My Documents\EFILive\V7.5\User Configuration

if your existing calc_pids.txt file has definitions in it, please post it here and I'll merge it with the new one.

[mr.prick]

How to match wideband output to {B3601} (https://forum.efilive.com/showthread.php?13229-How-to-match-wideband-output-to-B3601&highlight=b3601)

[Gav]

Hello, Sorry to jump on this thread ...
This hasnt worked for me (probably my error somewhere...)
I am trying to do autoVE with NGK AFX.
When i use the files above the wideband gauge reads 14 ish and the pid on laptop reads 12.2 ish....??.
So i just edited the text file to read what the gauge is reading and now got that working (I know there may be a slight error due to stoich values but i just wanted to test this first...)
I am getting very lost in this and need help to do the autovE tutorial with my NGK.
Any help would be greatly appreciated...My text file
# File details
# ------------
#
# This section defines various details about the file format.

*FILE

#Parameter Value Description
#---------- ---------------- ---------------------------------------------------
VERSION 7.1.1 File version
DECSEP . Decimal separator used in this file

# ================================================== ============================
# Units
# -------------------
# See sae_generic.txt for more information on the *UNITS section

*UNITS

#Code System Abbr Description
#-------- ---------- -------- -------------------------------------------------------------
None None "" "No units"
K Metric "K" "Degrees Kelvin"
R Imperial "R" "Degrees Rankine"
LAM None "LAM" "Lambda"
EQR None "EQR" "Equivalence Ratio"
E00 None "E00" "AFR based on E00"
E10 None "E10" "AFR based on E10"
E85 None "E85" "AFR based on E85"


# ================================================== ============================
# Add slot definitions here
# --------------------------------
# See sae_generic.txt for more information on "SLOT" formats
#
#Units Low High Fmt Expression
#------------ ------------- ------------- ---- --------------------------------------------------------------

*CLC-00-032
factor 0 4 .0 "{GM.EQIVRATIO}=1"

*CLC-00-899
AFR 9 20 .2 "(({EXT.AD1}-0.5)*2.75)+9"

*CLC-00-100
LAM 0.5 1.5 .4 "{CALC.AFR_NGK1}/14.57"
EQR 0.5 1.5 .4 "1/{CALC.WIDEBAND.LAM}"
E00 10.0 18.0 .4 "{CALC.WIDEBAND.LAM}*14.6"
E10 10.0 18.0 .4 "{CALC.WIDEBAND.LAM}*14.2"
E85 10.0 18.0 .4 "{CALC.WIDEBAND.LAM}*9.7"

*CLC-00-110
factor 0.5 1.5 .4 "((({EXT.AD1}-0.5)*2.75)+9)/14.63"

*CLC-00-120
factor 0.5 1.5 .4 "({SAE.LONGFT1}+{SAE.LONGFT2})/200+1"

*CLC-00-220
factor 0.5 1.5 .4 "iff({CALC.CL}, {CALC.LTFTBEN}, {CALC.WO2BEN})"

*CLC-00-273
C 0.0 100.0 .1 "{GM.DYNAIRTMP_DMA.C}"
F 40.0 220.0 .1 "{GM.DYNAIRTMP_DMA.F}"
K 280.0 380.0 .1 "{GM.DYNAIRTMP_DMA.C}+273.15"
R 500.0 680.0 .1 "{GM.DYNAIRTMP_DMA.F}+459.67"

*CLC-00-300
% 0.0 100.0 .2 "{SAE.MAF.gps}*{CALC.DAT.K}/{SAE.MAP.kPa}/{SAE.RPM}*3445.2/displacement()"
VE 0.0 2.468 .4 "{SAE.MAF.gps}*{CALC.DAT.K}/{SAE.MAP.kPa}/{SAE.RPM}*15"

*CLC-00-305
% 0.0 100.0 .2 "{CALC.SELBEN}*{CALC.VEN.%}"
VE 0.0 2.468 .4 "{CALC.SELBEN}*{CALC.VEN.VE}"

*CLC-00-310
gps 0.0 400.0 .1 "{GM.VETABLE_DMA.VE}/{CALC.DAT.K}*{SAE.MAP.kPa}*{SAE.RPM}/15"

*CLC-00-315
gps 0.0 400.0 .1 "{CALC.SELBEN}*{CALC.MAFN.gps}"

*CLC-00-430
VE 0.0 4.0 .4 "{GM.DYNCYLAIR_DMA}*{CALC.DAT.K}/{SAE.MAP.kPa}"

*CLC-00-435
gcyl 0.0 1.0 .4 "{GM.VETABLE_DMA.VE}/{CALC.DAT.K}*{SAE.MAP.kPa}"


# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
# See sae_generic.txt for more information on the *PRN section
#
#Code PRN SLOT Units System Description
#------------------------- ---- ------------ ---------------- ---------------- ------------------------------------------

CALC.CL F032 CLC-00-032 factor Tuning "Closed Loop (based on EQIVRATIO)"

CALC.WIDEBAND F100 CLC-00-100 "LAM,EQR,E00,E10,E85" Tuning "Wideband measured fueling"

CALC.WO2BEN F110 CLC-00-110 factor Tuning "BEN from WB"
CALC.LTFTBEN F120 CLC-00-120 factor Tuning "BEN from LTFT"
CALC.SELBEN F220 CLC-00-220 factor Tuning "BEN selected from LTFT or WB"

CALC.DAT F273 CLC-00-273 "C,F,K,R" Tuning "Dynamic Air Temperature"

CALC.VEN F300 CLC-00-300 "%,VE" Tuning "Calculated VE, not corrected"
CALC.VET F305 CLC-00-305 "%,VE" Tuning "Calculated VE, BEN corrected"

CALC.MAFN F310 CLC-00-310 gps Tuning "Calculated MAF, not corrected"
CALC.MAFT F315 CLC-00-315 gps Tuning "Calculated MAF, BEN corrected"

CALC.VEDCA F430 CLC-00-430 VE Tuning "Calculated VE (from DCA)"
CALC.DCAVE F435 CLC-00-435 gcyl Tuning "Calculated DCA (from VE)"
CALC.NGK F320 CLC-00-899 AFR Fuel "AFR from NGK"

Am i going about this all wrong and have no idea how to get the BEN part working as well.....:confused::confused:
Regards
GAv

[lobie]

I'm new to all this but I've been using the CALC.VET with good results. I also have the AFX.
I'm sure Joecar will chime in soon.

[mr.prick]

post #4 has all you need to correct your calc_pid.

if there is a voltage offset, you need to calibrate the AD inputs.

[joecar]

Hi Gav,

Are you using the pid CALC.WIDEBAND.LAM...?

In your calc_pids.txt, edit CLC-00-110 to read as follows:


*CLC-00-110
factor 0.5 1.5 .4 "{GM.EQIVRATIO}*{CALC.WIDEBAND.LAM}"


and delete this:


*CLC-00-899
AFR 9 20 .2 "(({EXT.AD1}-0.5)*2.75)+9"


and delete this:


CALC.NGK F320 CLC-00-899 AFR Fuel "AFR from NGK"

[joecar]

And go see this:

How to match wideband output to {B3601} (https://forum.efilive.com/showthread.php?13229-How-to-match-wideband-output-to-B3601&highlight=b3601)

[joecar]

I'm new to all this but I've been using the CALC.VET with good results. I also have the AFX.
I'm sure Joecar will chime in soon.
If you have an NGK AFX then you need this calc_pids.txt file (attached)...

and you would use the pid CALC.WO2BEN for tuning, and CALC.WIDEBAND.E00 or .E10 or .E85 (depending on fuel) for viewing the AFR.

[Gav]

Hello and thanks for help.
yes I read and tried that text file but I think the voltage offset of ad1 is throwing it out. 0.5 to 4.5
I will retry the xls input again, I dont know how to calibrate the ad inputs though.
regards gav

[joecar]

Hello and thanks for help.
yes I read and tried that text file but I think the voltage offset of ad1 is throwing it out. 0.5 to 4.5
I will retry the xls input again, I dont know how to calibrate the ad inputs though.
regards gavYou measured with a DMM and see how much voltage offset...?

[Gav]

Hi Joe,
Sorry what i meant is that from the Manuel :
'Vout is the analog voltage of the AFRM(0.5v to 4.5v)' So it must output 0.5v at 9 AFR and 4.5 at 20 AFR. By the way it is the 2nd version i think of the NGK AFX.
Also from the book:
Gasoline AFR = {(Vout-0.5)x2.75}+9
Lambda = {(Vout-0.5v)x0.189)}+0.62

Regards
Gav

[joecar]

Hi Joe,
Sorry what i meant is that from the Manuel :
'Vout is the analog voltage of the AFRM(0.5v to 4.5v)' So it must output 0.5v at 9 AFR and 4.5 at 20 AFR. By the way it is the 2nd version i think of the NGK AFX.
Also from the book:
Gasoline AFR = {(Vout-0.5)x2.75}+9
Lambda = {(Vout-0.5v)x0.189)}+0.62

Regards
GavPost the user manual you have.

Is it the same as this one (see page 11): afx_tuning_manual_rev_06.pdf (http://www.ngksparkplugs.com/pdf/afx_tuning_manual_rev_06.pdf)

[darcy]

Sounds like its a NTK AFRX, Joe.

Gav, have a look at this thread: https://forum.efilive.com/showthread.php?24432-calculated-pid-not-valid-for-NGK-NTK-Air-Fuel-Ratio-Monitor

[Gav]

Hi,
yes it is the one darcy posted. In that thread shows the user manual and shows designed to run on 14.7 as stoich. I thought I was losing it as most other people were getting it to work with a different formula....might have to alter the text file for afr and ben then?
thanks for help this far though, regards gav

[joecar]

Ah, it's an NTK and not an NGK... (the equation is different).