Anyone have a NTK AFX calc pid for E85?

[Hotrodcorvette]

Hi All,

Just switched the vette to E85 and trying to iron out the tune with Autove. I have read the calc pid threads for about three hours and to be honest my head is swimming. Anyone have a pid already done for E85 with the afx wideband?

If not I will keep working on trying to write one.

Thanks for your time,
Tyler

[Hotrodcorvette]

Oh and I think I figured out the equation.... {ext.ad}* 0.9389 + 6.064

I am just lost on the programming side.

[joecar]

What is the equation for lambda given in your AFX user manual pdf...?

[joecar]

{EXT.AD1}*0.096+0.62 = Lamda

See this thread: NTK-AFX-Wiring-and-PID-Advice-Needed

[mr.prick]

use this spreadsheet.

How to match wideband output to {B3601}

[Taz]

No E85 available here ... so I have no direct experience ... but you will be near the resolution threshold of the AFX when monitoring E85.

AFX has an approximate working range of:

• AFR = 9.00 to 16.00
• Lambda = 0.62 to 1.10
• EQR = 1.61 to 0.91

[Hotrodcorvette]

Thank you to all for the input. I am going to block some time and try again this weekend.

Starting to wonder if this is the smart approach? should I be focusing my efforts on tuning with lambda or eqr instead of AFR?

I measured my fuel and it is really E93... I imagine I will also use E7x something at other stations. Would tuning in EQR OR lambda make it easier with the fuel % swings as I would not need a custom PID for each? My goal is to stay with one station most of the time.

Thanks again,

Tyler

[joecar]

Find out the stoich AFR for the fuel you're running, and enter this value into B3601 in your tune file.

Then perform all tuning using either EQR or Lambda...



Have a read of post #1 of this thread: Calc-VET-correcting-MAF-and-calculating-VE-(in-single-log)

scroll down in post #1 to this section: II. PROCEDURE for ANALOG WIDEBAND or V1

your CALC.WO2BEN would be defined as "{GM.EQIVRATIO}*{CALC.LAMBDA}"

where CALC.LAMBDA would be defined as "{EXT.AD1}*0.096+0.62" (you will have to edit your calc_pids.txt file to define this).

[joecar]

Actually, you could define it in terms of the NGK AFR pid (since the NGK has the same voltage:AFR equation as the NTK AFX):

WO2BEN = "{GM.EQIVRATIO}*{CALC.AFR_NGK1}/14.57"


The calc_pid.txt file defining this can be found in post #8 of this thread: NTK-AFX-Wiring-and-PID-Advice-Needed

[Hotrodcorvette]

I spent some time this weekend trying again. I updated the calculated PIDs as suggested in the last post from Joe, I also tried replacing the 14.57 AFR with 9.4 in the Calc Pid to match the AFR of my E93 mixture commanded in B3601 (both attached for reference). Neither seemed to make a difference and the wideband readings are still way out of wack showing 14.X AFRs when I am commanding 9.X AFRs.

What else am I missing? Car will start but still smoking a lot and I can't do an AutoVE until I get this wideband sorted.

Thanks,
Tyler