We all have to stop using AFR and start using Stoich or Lambda.
A wideband O2 sensor is not an AFR meter, it's a Lambda meter and then converted to AFR for a gauge or data reading. The wide band controller sets Lamda to 1.0 for the fuel you enter. 14.7 for gas but that is hard to find anymore. For E10 I have seen numbers from 13.8 to 14.3 the real issue is what do you have in your tank? Look at the pump it say CAN contain up to 10 % ethanol.
SO if your wide band is set to 14.7 and the AFR or Stioich in your bin is 14.7 then your analogue wideband says 14.6 AFR, it really isn't 14.6, but is actually 14.1 because the narrow band has corrected to Stoich of E10 fuel. Your LTFT are high... LTFT can be off in data as well becuse of BLM learn stored in ECM/PCM.
Don't beleive me? Hook your Lc-1 serial cable up to logworks, it's a true reading and has no analog voltage or ground issues, then change it over to Lambda!
Narrow band O2 sensor is desinged to correct to Stoich, it will correct fueling if you use gas or E10, for that matter it will correct to Stoich of any fuel. There's where all the STFT and LTFT come into play.
To tune with a wide band O2 sesnor data and adjust the VE table you need to disable all O2 correction. Some bins can disable Closed Loop enable for both, but some only turn off LTFT, so you still have STFT. Easiest way I found without disconnecting O2 sesnor and codes is set INT/STFT min and max to 128, also set BLM/LTFT min max to 128. Now you have no narrow band O2 sesnor feedback and are getting the fueling straight from VE tables. Clear BLM learn...
For the more common E10 fuel set Stoich AFR in bin set to 14.2 (close, see above) and Wide Band set for 14.2 and use Lambda which should be 1.00. 1.01 is lean and .99 is rich, .85 comes out to about right for 12.5-9 AFR for PE...
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