Hondata

I am confused as to what AF ratio I should be looking for in my datalogs when tuning on e85. I have a digital wideband gauge also, and it appears that the readings it gives me are far different from what the AF ratio shown in my datalogs. It has me wondering, in SManager is it looking for the actual ratio for e85 (9.8:1 or something being stoich) but somehow my gauge is actually reading 14.7:1?

It was my understanding that, since the O2 sensor reads oxygen after combustion, the reading should be the same whether it is burning 87 octane or e85. Is that not the case? Or is it actually that some conversion factor is needed to make the wideband read out comparable AF's as for gasoline?

See the attached image I am looking at, just a datalog (also attached) of the car idling poorly. The datalog always shows my AF in the 10's where on my wideband I am in the 15's. What am I missing?

Did you change the wideband output voltage to ethanol? If not, then it is the wideband or wideband output because SManager is not converting the lambda for ethanol.

No I did not, do I do this by changing the voltage offset? What is the correct setting to use?

Thanks,

No, I'm not suggesting that you should do so. I believe your wideband voltage output is not correct.

Okay I see what you are saying. I am not sure how to figure this out since I did not do the wideband install or wiring. But it looks like whatever signal it is getting in SManager for "Lambda Voltage" is only reading from 0 to 1.5 volts, with 1.5 being rich. So it's not even a wideband signal. Then when it converts into AF ratio, it's completely off. I am attaching a datalog of a 3rd gear pull so you can see what I mean.

Any suggestion for how I can get this 0-1.5V signal to show the actual A/F ratio, or is there any way to find out whether the wideband is even wired to the S300?

Thanks

How are you reading the wideband? ie how is it wired to the ECU/s300? In the datalog it looks plausible, but you'd need to compare the wideband display with the SManager datalogging to tell how accurate the input it.

That's sort of the problem, I'm not sure how or if the wideband is even wired into the ECU. When I found the wideband lambda sensor in Smanager I assumed that was it, but it appears to be a narrowband signal.

I checked every other analog and digital input in Smanager to see if any of them are getting a signal, and it does not appear so in the datalogs.

After taking some readings from my wideband gauge and comparing it to the Lambda voltage showing in SManager, I believe this is what the voltages are equating to in actual AFR...

Volts----AFR
0.00-----17
0.25-----16
0.50-----15
0.75-----14
1.00-----13
1.25-----12
1.50-----11
1.75-----10

Or something to that effect. It may actually be richer than that over the 1V mark. Is there any way to set this to read out AF in SManager like this to aid in my tuning?

Thanks,

Trace the wiring from the wideband to the S300, and also verify the output voltage table (the table you gave looks inverted).